lavc: move decoding-related code from utils.c to a new file

3 files changed, 925 insertions, 889 deletions

diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index fe723155a5..dee3d1398e 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -23,6 +23,7 @@ OBJS = allcodecs.o                                                      \
        bsf.o                                                            \
        codec_desc.o                                                     \
        d3d11va.o                                                        \
+       decode.o                                                         \
        dirac.o                                                          \
        dv_profile.o                                                     \
        encode.o                                                         \
diff --git a/libavcodec/decode.c b/libavcodec/decode.c
new file mode 100644
index 0000000000..42bcee2d17
--- /dev/null
+++ b/libavcodec/decode.c
@@ -0,0 +1,924 @@
+/*
+ * generic decoding-related code
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdint.h>
+#include <string.h>
+
+#include "config.h"
+
+#include "libavutil/avassert.h"
+#include "libavutil/common.h"
+#include "libavutil/frame.h"
+#include "libavutil/hwcontext.h"
+#include "libavutil/imgutils.h"
+
+#include "avcodec.h"
+#include "bytestream.h"
+#include "internal.h"
+#include "thread.h"
+
+static int apply_param_change(AVCodecContext *avctx, AVPacket *avpkt)
+{
+    int size = 0, ret;
+    const uint8_t *data;
+    uint32_t flags;
+
+    data = av_packet_get_side_data(avpkt, AV_PKT_DATA_PARAM_CHANGE, &size);
+    if (!data)
+        return 0;
+
+    if (!(avctx->codec->capabilities & AV_CODEC_CAP_PARAM_CHANGE)) {
+        av_log(avctx, AV_LOG_ERROR, "This decoder does not support parameter "
+               "changes, but PARAM_CHANGE side data was sent to it.\n");
+        ret = AVERROR(EINVAL);
+        goto fail2;
+    }
+
+    if (size < 4)
+        goto fail;
+
+    flags = bytestream_get_le32(&data);
+    size -= 4;
+
+    if (flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT) {
+        if (size < 4)
+            goto fail;
+        avctx->channels = bytestream_get_le32(&data);
+        size -= 4;
+    }
+    if (flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT) {
+        if (size < 8)
+            goto fail;
+        avctx->channel_layout = bytestream_get_le64(&data);
+        size -= 8;
+    }
+    if (flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE) {
+        if (size < 4)
+            goto fail;
+        avctx->sample_rate = bytestream_get_le32(&data);
+        size -= 4;
+    }
+    if (flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS) {
+        if (size < 8)
+            goto fail;
+        avctx->width  = bytestream_get_le32(&data);
+        avctx->height = bytestream_get_le32(&data);
+        size -= 8;
+        ret = ff_set_dimensions(avctx, avctx->width, avctx->height);
+        if (ret < 0)
+            goto fail2;
+    }
+
+    return 0;
+fail:
+    av_log(avctx, AV_LOG_ERROR, "PARAM_CHANGE side data too small.\n");
+    ret = AVERROR_INVALIDDATA;
+fail2:
+    if (ret < 0) {
+        av_log(avctx, AV_LOG_ERROR, "Error applying parameter changes.\n");
+        if (avctx->err_recognition & AV_EF_EXPLODE)
+            return ret;
+    }
+    return 0;
+}
+
+static int unrefcount_frame(AVCodecInternal *avci, AVFrame *frame)
+{
+    int ret;
+
+    /* move the original frame to our backup */
+    av_frame_unref(avci->to_free);
+    av_frame_move_ref(avci->to_free, frame);
+
+    /* now copy everything except the AVBufferRefs back
+     * note that we make a COPY of the side data, so calling av_frame_free() on
+     * the caller's frame will work properly */
+    ret = av_frame_copy_props(frame, avci->to_free);
+    if (ret < 0)
+        return ret;
+
+    memcpy(frame->data,     avci->to_free->data,     sizeof(frame->data));
+    memcpy(frame->linesize, avci->to_free->linesize, sizeof(frame->linesize));
+    if (avci->to_free->extended_data != avci->to_free->data) {
+        int planes = av_get_channel_layout_nb_channels(avci->to_free->channel_layout);
+        int size   = planes * sizeof(*frame->extended_data);
+
+        if (!size) {
+            av_frame_unref(frame);
+            return AVERROR_BUG;
+        }
+
+        frame->extended_data = av_malloc(size);
+        if (!frame->extended_data) {
+            av_frame_unref(frame);
+            return AVERROR(ENOMEM);
+        }
+        memcpy(frame->extended_data, avci->to_free->extended_data,
+               size);
+    } else
+        frame->extended_data = frame->data;
+
+    frame->format         = avci->to_free->format;
+    frame->width          = avci->to_free->width;
+    frame->height         = avci->to_free->height;
+    frame->channel_layout = avci->to_free->channel_layout;
+    frame->nb_samples     = avci->to_free->nb_samples;
+
+    return 0;
+}
+
+static int do_decode(AVCodecContext *avctx, AVPacket *pkt)
+{
+    int got_frame;
+    int ret;
+
+    av_assert0(!avctx->internal->buffer_frame->buf[0]);
+
+    if (!pkt)
+        pkt = avctx->internal->buffer_pkt;
+
+    // This is the lesser evil. The field is for compatibility with legacy users
+    // of the legacy API, and users using the new API should not be forced to
+    // even know about this field.
+    avctx->refcounted_frames = 1;
+
+    // Some codecs (at least wma lossless) will crash when feeding drain packets
+    // after EOF was signaled.
+    if (avctx->internal->draining_done)
+        return AVERROR_EOF;
+
+    if (avctx->codec_type == AVMEDIA_TYPE_VIDEO) {
+        ret = avcodec_decode_video2(avctx, avctx->internal->buffer_frame,
+                                    &got_frame, pkt);
+        if (ret >= 0)
+            ret = pkt->size;
+    } else if (avctx->codec_type == AVMEDIA_TYPE_AUDIO) {
+        ret = avcodec_decode_audio4(avctx, avctx->internal->buffer_frame,
+                                    &got_frame, pkt);
+    } else {
+        ret = AVERROR(EINVAL);
+    }
+
+    if (ret < 0)
+        return ret;
+
+    if (avctx->internal->draining && !got_frame)
+        avctx->internal->draining_done = 1;
+
+    if (ret >= pkt->size) {
+        av_packet_unref(avctx->internal->buffer_pkt);
+    } else {
+        int consumed = ret;
+
+        if (pkt != avctx->internal->buffer_pkt) {
+            av_packet_unref(avctx->internal->buffer_pkt);
+            if ((ret = av_packet_ref(avctx->internal->buffer_pkt, pkt)) < 0)
+                return ret;
+        }
+
+        avctx->internal->buffer_pkt->data += consumed;
+        avctx->internal->buffer_pkt->size -= consumed;
+        avctx->internal->buffer_pkt->pts   = AV_NOPTS_VALUE;
+        avctx->internal->buffer_pkt->dts   = AV_NOPTS_VALUE;
+    }
+
+    if (got_frame)
+        av_assert0(avctx->internal->buffer_frame->buf[0]);
+
+    return 0;
+}
+
+int attribute_align_arg avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
+{
+    int ret;
+
+    if (!avcodec_is_open(avctx) || !av_codec_is_decoder(avctx->codec))
+        return AVERROR(EINVAL);
+
+    if (avctx->internal->draining)
+        return AVERROR_EOF;
+
+    if (!avpkt || !avpkt->size) {
+        avctx->internal->draining = 1;
+        avpkt = NULL;
+
+        if (!(avctx->codec->capabilities & AV_CODEC_CAP_DELAY))
+            return 0;
+    }
+
+    if (avctx->codec->send_packet) {
+        if (avpkt) {
+            ret = apply_param_change(avctx, (AVPacket *)avpkt);
+            if (ret < 0)
+                return ret;
+        }
+        return avctx->codec->send_packet(avctx, avpkt);
+    }
+
+    // Emulation via old API. Assume avpkt is likely not refcounted, while
+    // decoder output is always refcounted, and avoid copying.
+
+    if (avctx->internal->buffer_pkt->size || avctx->internal->buffer_frame->buf[0])
+        return AVERROR(EAGAIN);
+
+    // The goal is decoding the first frame of the packet without using memcpy,
+    // because the common case is having only 1 frame per packet (especially
+    // with video, but audio too). In other cases, it can't be avoided, unless
+    // the user is feeding refcounted packets.
+    return do_decode(avctx, (AVPacket *)avpkt);
+}
+
+int attribute_align_arg avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
+{
+    int ret;
+
+    av_frame_unref(frame);
+
+    if (!avcodec_is_open(avctx) || !av_codec_is_decoder(avctx->codec))
+        return AVERROR(EINVAL);
+
+    if (avctx->codec->receive_frame) {
+        if (avctx->internal->draining && !(avctx->codec->capabilities & AV_CODEC_CAP_DELAY))
+            return AVERROR_EOF;
+        return avctx->codec->receive_frame(avctx, frame);
+    }
+
+    // Emulation via old API.
+
+    if (!avctx->internal->buffer_frame->buf[0]) {
+        if (!avctx->internal->buffer_pkt->size && !avctx->internal->draining)
+            return AVERROR(EAGAIN);
+
+        while (1) {
+            if ((ret = do_decode(avctx, avctx->internal->buffer_pkt)) < 0) {
+                av_packet_unref(avctx->internal->buffer_pkt);
+                return ret;
+            }
+            // Some audio decoders may consume partial data without returning
+            // a frame (fate-wmapro-2ch). There is no way to make the caller
+            // call avcodec_receive_frame() again without returning a frame,
+            // so try to decode more in these cases.
+            if (avctx->internal->buffer_frame->buf[0] ||
+                !avctx->internal->buffer_pkt->size)
+                break;
+        }
+    }
+
+    if (!avctx->internal->buffer_frame->buf[0])
+        return avctx->internal->draining ? AVERROR_EOF : AVERROR(EAGAIN);
+
+    av_frame_move_ref(frame, avctx->internal->buffer_frame);
+    return 0;
+}
+
+int attribute_align_arg avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
+                                              int *got_picture_ptr,
+                                              AVPacket *avpkt)
+{
+    AVCodecInternal *avci = avctx->internal;
+    int ret;
+
+    *got_picture_ptr = 0;
+    if ((avctx->coded_width || avctx->coded_height) && av_image_check_size(avctx->coded_width, avctx->coded_height, 0, avctx))
+        return -1;
+
+    if (!avctx->codec->decode) {
+        av_log(avctx, AV_LOG_ERROR, "This decoder requires using the avcodec_send_packet() API.\n");
+        return AVERROR(ENOSYS);
+    }
+
+    avctx->internal->pkt = avpkt;
+    ret = apply_param_change(avctx, avpkt);
+    if (ret < 0)
+        return ret;
+
+    av_frame_unref(picture);
+
+    if ((avctx->codec->capabilities & AV_CODEC_CAP_DELAY) || avpkt->size ||
+        (avctx->active_thread_type & FF_THREAD_FRAME)) {
+        if (HAVE_THREADS && avctx->active_thread_type & FF_THREAD_FRAME)
+            ret = ff_thread_decode_frame(avctx, picture, got_picture_ptr,
+                                         avpkt);
+        else {
+            ret = avctx->codec->decode(avctx, picture, got_picture_ptr,
+                                       avpkt);
+            if (!(avctx->codec->caps_internal & FF_CODEC_CAP_SETS_PKT_DTS))
+                picture->pkt_dts = avpkt->dts;
+            /* get_buffer is supposed to set frame parameters */
+            if (!(avctx->codec->capabilities & AV_CODEC_CAP_DR1)) {
+                picture->sample_aspect_ratio = avctx->sample_aspect_ratio;
+                picture->width               = avctx->width;
+                picture->height              = avctx->height;
+                picture->format              = avctx->pix_fmt;
+            }
+        }
+
+        emms_c(); //needed to avoid an emms_c() call before every return;
+
+        if (*got_picture_ptr) {
+            if (!avctx->refcounted_frames) {
+                int err = unrefcount_frame(avci, picture);
+                if (err < 0)
+                    return err;
+            }
+
+            avctx->frame_number++;
+        } else
+            av_frame_unref(picture);
+    } else
+        ret = 0;
+
+#if FF_API_AVCTX_TIMEBASE
+    if (avctx->framerate.num > 0 && avctx->framerate.den > 0)
+        avctx->time_base = av_inv_q(avctx->framerate);
+#endif
+
+    return ret;
+}
+
+int attribute_align_arg avcodec_decode_audio4(AVCodecContext *avctx,
+                                              AVFrame *frame,
+                                              int *got_frame_ptr,
+                                              AVPacket *avpkt)
+{
+    AVCodecInternal *avci = avctx->internal;
+    int ret = 0;
+
+    *got_frame_ptr = 0;
+
+    if (!avctx->codec->decode) {
+        av_log(avctx, AV_LOG_ERROR, "This decoder requires using the avcodec_send_packet() API.\n");
+        return AVERROR(ENOSYS);
+    }
+
+    avctx->internal->pkt = avpkt;
+
+    if (!avpkt->data && avpkt->size) {
+        av_log(avctx, AV_LOG_ERROR, "invalid packet: NULL data, size != 0\n");
+        return AVERROR(EINVAL);
+    }
+
+    ret = apply_param_change(avctx, avpkt);
+    if (ret < 0)
+        return ret;
+
+    av_frame_unref(frame);
+
+    if ((avctx->codec->capabilities & AV_CODEC_CAP_DELAY) || avpkt->size) {
+        ret = avctx->codec->decode(avctx, frame, got_frame_ptr, avpkt);
+        if (ret >= 0 && *got_frame_ptr) {
+            avctx->frame_number++;
+            frame->pkt_dts = avpkt->dts;
+            if (frame->format == AV_SAMPLE_FMT_NONE)
+                frame->format = avctx->sample_fmt;
+
+            if (!avctx->refcounted_frames) {
+                int err = unrefcount_frame(avci, frame);
+                if (err < 0)
+                    return err;
+            }
+        } else
+            av_frame_unref(frame);
+    }
+
+
+    return ret;
+}
+
+int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
+                             int *got_sub_ptr,
+                             AVPacket *avpkt)
+{
+    int ret;
+
+    avctx->internal->pkt = avpkt;
+    *got_sub_ptr = 0;
+    ret = avctx->codec->decode(avctx, sub, got_sub_ptr, avpkt);
+    if (*got_sub_ptr)
+        avctx->frame_number++;
+    return ret;
+}
+
+static int is_hwaccel_pix_fmt(enum AVPixelFormat pix_fmt)
+{
+    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
+    return desc->flags & AV_PIX_FMT_FLAG_HWACCEL;
+}
+
+enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
+{
+    while (*fmt != AV_PIX_FMT_NONE && is_hwaccel_pix_fmt(*fmt))
+        ++fmt;
+    return fmt[0];
+}
+
+static AVHWAccel *find_hwaccel(enum AVCodecID codec_id,
+                               enum AVPixelFormat pix_fmt)
+{
+    AVHWAccel *hwaccel = NULL;
+
+    while ((hwaccel = av_hwaccel_next(hwaccel)))
+        if (hwaccel->id == codec_id
+            && hwaccel->pix_fmt == pix_fmt)
+            return hwaccel;
+    return NULL;
+}
+
+static int setup_hwaccel(AVCodecContext *avctx,
+                         const enum AVPixelFormat fmt,
+                         const char *name)
+{
+    AVHWAccel *hwa = find_hwaccel(avctx->codec_id, fmt);
+    int ret        = 0;
+
+    if (!hwa) {
+        av_log(avctx, AV_LOG_ERROR,
+               "Could not find an AVHWAccel for the pixel format: %s",
+               name);
+        return AVERROR(ENOENT);
+    }
+
+    if (hwa->priv_data_size) {
+        avctx->internal->hwaccel_priv_data = av_mallocz(hwa->priv_data_size);
+        if (!avctx->internal->hwaccel_priv_data)
+            return AVERROR(ENOMEM);
+    }
+
+    if (hwa->init) {
+        ret = hwa->init(avctx);
+        if (ret < 0) {
+            av_freep(&avctx->internal->hwaccel_priv_data);
+            return ret;
+        }
+    }
+
+    avctx->hwaccel = hwa;
+
+    return 0;
+}
+
+int ff_get_format(AVCodecContext *avctx, const enum AVPixelFormat *fmt)
+{
+    const AVPixFmtDescriptor *desc;
+    enum AVPixelFormat *choices;
+    enum AVPixelFormat ret;
+    unsigned n = 0;
+
+    while (fmt[n] != AV_PIX_FMT_NONE)
+        ++n;
+
+    av_assert0(n >= 1);
+    avctx->sw_pix_fmt = fmt[n - 1];
+    av_assert2(!is_hwaccel_pix_fmt(avctx->sw_pix_fmt));
+
+    choices = av_malloc_array(n + 1, sizeof(*choices));
+    if (!choices)
+        return AV_PIX_FMT_NONE;
+
+    memcpy(choices, fmt, (n + 1) * sizeof(*choices));
+
+    for (;;) {
+        if (avctx->hwaccel && avctx->hwaccel->uninit)
+            avctx->hwaccel->uninit(avctx);
+        av_freep(&avctx->internal->hwaccel_priv_data);
+        avctx->hwaccel = NULL;
+
+        av_buffer_unref(&avctx->hw_frames_ctx);
+
+        ret = avctx->get_format(avctx, choices);
+
+        desc = av_pix_fmt_desc_get(ret);
+        if (!desc) {
+            ret = AV_PIX_FMT_NONE;
+            break;
+        }
+
+        if (!(desc->flags & AV_PIX_FMT_FLAG_HWACCEL))
+            break;
+
+        if (avctx->hw_frames_ctx) {
+            AVHWFramesContext *hw_frames_ctx = (AVHWFramesContext*)avctx->hw_frames_ctx->data;
+            if (hw_frames_ctx->format != ret) {
+                av_log(avctx, AV_LOG_ERROR, "Format returned from get_buffer() "
+                       "does not match the format of provided AVHWFramesContext\n");
+                ret = AV_PIX_FMT_NONE;
+                break;
+            }
+        }
+
+        if (!setup_hwaccel(avctx, ret, desc->name))
+            break;
+
+        /* Remove failed hwaccel from choices */
+        for (n = 0; choices[n] != ret; n++)
+            av_assert0(choices[n] != AV_PIX_FMT_NONE);
+
+        do
+            choices[n] = choices[n + 1];
+        while (choices[n++] != AV_PIX_FMT_NONE);
+    }
+
+    av_freep(&choices);
+    return ret;
+}
+
+static int update_frame_pool(AVCodecContext *avctx, AVFrame *frame)
+{
+    FramePool *pool = avctx->internal->pool;
+    int i, ret;
+
+    switch (avctx->codec_type) {
+    case AVMEDIA_TYPE_VIDEO: {
+        uint8_t *data[4];
+        int linesize[4];
+        int size[4] = { 0 };
+        int w = frame->width;
+        int h = frame->height;
+        int tmpsize, unaligned;
+
+        if (pool->format == frame->format &&
+            pool->width == frame->width && pool->height == frame->height)
+            return 0;
+
+        avcodec_align_dimensions2(avctx, &w, &h, pool->stride_align);
+
+        do {
+            // NOTE: do not align linesizes individually, this breaks e.g. assumptions
+            // that linesize[0] == 2*linesize[1] in the MPEG-encoder for 4:2:2
+            av_image_fill_linesizes(linesize, avctx->pix_fmt, w);
+            // increase alignment of w for next try (rhs gives the lowest bit set in w)
+            w += w & ~(w - 1);
+
+            unaligned = 0;
+            for (i = 0; i < 4; i++)
+                unaligned |= linesize[i] % pool->stride_align[i];
+        } while (unaligned);
+
+        tmpsize = av_image_fill_pointers(data, avctx->pix_fmt, h,
+                                         NULL, linesize);
+        if (tmpsize < 0)
+            return -1;
+
+        for (i = 0; i < 3 && data[i + 1]; i++)
+            size[i] = data[i + 1] - data[i];
+        size[i] = tmpsize - (data[i] - data[0]);
+
+        for (i = 0; i < 4; i++) {
+            av_buffer_pool_uninit(&pool->pools[i]);
+            pool->linesize[i] = linesize[i];
+            if (size[i]) {
+                pool->pools[i] = av_buffer_pool_init(size[i] + 16, NULL);
+                if (!pool->pools[i]) {
+                    ret = AVERROR(ENOMEM);
+                    goto fail;
+                }
+            }
+        }
+        pool->format = frame->format;
+        pool->width  = frame->width;
+        pool->height = frame->height;
+
+        break;
+        }
+    case AVMEDIA_TYPE_AUDIO: {
+        int ch     = av_get_channel_layout_nb_channels(frame->channel_layout);
+        int planar = av_sample_fmt_is_planar(frame->format);
+        int planes = planar ? ch : 1;
+
+        if (pool->format == frame->format && pool->planes == planes &&
+            pool->channels == ch && frame->nb_samples == pool->samples)
+            return 0;
+
+        av_buffer_pool_uninit(&pool->pools[0]);
+        ret = av_samples_get_buffer_size(&pool->linesize[0], ch,
+                                         frame->nb_samples, frame->format, 0);
+        if (ret < 0)
+            goto fail;
+
+        pool->pools[0] = av_buffer_pool_init(pool->linesize[0], NULL);
+        if (!pool->pools[0]) {
+            ret = AVERROR(ENOMEM);
+            goto fail;
+        }
+
+        pool->format     = frame->format;
+        pool->planes     = planes;
+        pool->channels   = ch;
+        pool->samples = frame->nb_samples;
+        break;
+        }
+    default: av_assert0(0);
+    }
+    return 0;
+fail:
+    for (i = 0; i < 4; i++)
+        av_buffer_pool_uninit(&pool->pools[i]);
+    pool->format = -1;
+    pool->planes = pool->channels = pool->samples = 0;
+    pool->width  = pool->height = 0;
+    return ret;
+}
+
+static int audio_get_buffer(AVCodecContext *avctx, AVFrame *frame)
+{
+    FramePool *pool = avctx->internal->pool;
+    int planes = pool->planes;
+    int i;
+
+    frame->linesize[0] = pool->linesize[0];
+
+    if (planes > AV_NUM_DATA_POINTERS) {
+        frame->extended_data = av_mallocz(planes * sizeof(*frame->extended_data));
+        frame->nb_extended_buf = planes - AV_NUM_DATA_POINTERS;
+        frame->extended_buf  = av_mallocz(frame->nb_extended_buf *
+                                          sizeof(*frame->extended_buf));
+        if (!frame->extended_data || !frame->extended_buf) {
+            av_freep(&frame->extended_data);
+            av_freep(&frame->extended_buf);
+            return AVERROR(ENOMEM);
+        }
+    } else
+        frame->extended_data = frame->data;
+
+    for (i = 0; i < FFMIN(planes, AV_NUM_DATA_POINTERS); i++) {
+        frame->buf[i] = av_buffer_pool_get(pool->pools[0]);
+        if (!frame->buf[i])
+            goto fail;
+        frame->extended_data[i] = frame->data[i] = frame->buf[i]->data;
+    }
+    for (i = 0; i < frame->nb_extended_buf; i++) {
+        frame->extended_buf[i] = av_buffer_pool_get(pool->pools[0]);
+        if (!frame->extended_buf[i])
+            goto fail;
+        frame->extended_data[i + AV_NUM_DATA_POINTERS] = frame->extended_buf[i]->data;
+    }
+
+    if (avctx->debug & FF_DEBUG_BUFFERS)
+        av_log(avctx, AV_LOG_DEBUG, "default_get_buffer called on frame %p", frame);
+
+    return 0;
+fail:
+    av_frame_unref(frame);
+    return AVERROR(ENOMEM);
+}
+
+static int video_get_buffer(AVCodecContext *s, AVFrame *pic)
+{
+    FramePool *pool = s->internal->pool;
+    int i;
+
+    if (pic->data[0]) {
+        av_log(s, AV_LOG_ERROR, "pic->data[0]!=NULL in avcodec_default_get_buffer\n");
+        return -1;
+    }
+
+    memset(pic->data, 0, sizeof(pic->data));
+    pic->extended_data = pic->data;
+
+    for (i = 0; i < 4 && pool->pools[i]; i++) {
+        pic->linesize[i] = pool->linesize[i];
+
+        pic->buf[i] = av_buffer_pool_get(pool->pools[i]);
+        if (!pic->buf[i])
+            goto fail;
+
+        pic->data[i] = pic->buf[i]->data;
+    }
+    for (; i < AV_NUM_DATA_POINTERS; i++) {
+        pic->data[i] = NULL;
+        pic->linesize[i] = 0;
+    }
+    if (pic->data[1] && !pic->data[2])
+        avpriv_set_systematic_pal2((uint32_t *)pic->data[1], s->pix_fmt);
+
+    if (s->debug & FF_DEBUG_BUFFERS)
+        av_log(s, AV_LOG_DEBUG, "default_get_buffer called on pic %p\n", pic);
+
+    return 0;
+fail:
+    av_frame_unref(pic);
+    return AVERROR(ENOMEM);
+}
+
+int avcodec_default_get_buffer2(AVCodecContext *avctx, AVFrame *frame, int flags)
+{
+    int ret;
+
+    if (avctx->hw_frames_ctx)
+        return av_hwframe_get_buffer(avctx->hw_frames_ctx, frame, 0);
+
+    if ((ret = update_frame_pool(avctx, frame)) < 0)
+        return ret;
+
+    switch (avctx->codec_type) {
+    case AVMEDIA_TYPE_VIDEO:
+        return video_get_buffer(avctx, frame);
+    case AVMEDIA_TYPE_AUDIO:
+        return audio_get_buffer(avctx, frame);
+    default:
+        return -1;
+    }
+}
+
+int ff_decode_frame_props(AVCodecContext *avctx, AVFrame *frame)
+{
+    AVPacket *pkt = avctx->internal->pkt;
+    int i;
+    struct {
+        enum AVPacketSideDataType packet;
+        enum AVFrameSideDataType frame;
+    } sd[] = {
+        { AV_PKT_DATA_REPLAYGAIN ,   AV_FRAME_DATA_REPLAYGAIN },
+        { AV_PKT_DATA_DISPLAYMATRIX, AV_FRAME_DATA_DISPLAYMATRIX },
+        { AV_PKT_DATA_STEREO3D,      AV_FRAME_DATA_STEREO3D },
+        { AV_PKT_DATA_AUDIO_SERVICE_TYPE, AV_FRAME_DATA_AUDIO_SERVICE_TYPE },
+    };
+
+    frame->color_primaries = avctx->color_primaries;
+    frame->color_trc       = avctx->color_trc;
+    frame->colorspace      = avctx->colorspace;
+    frame->color_range     = avctx->color_range;
+    frame->chroma_location = avctx->chroma_sample_location;
+
+    frame->reordered_opaque = avctx->reordered_opaque;
+    if (!pkt) {
+#if FF_API_PKT_PTS
+FF_DISABLE_DEPRECATION_WARNINGS
+        frame->pkt_pts = AV_NOPTS_VALUE;
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
+        frame->pts     = AV_NOPTS_VALUE;
+        return 0;
+    }
+
+#if FF_API_PKT_PTS
+FF_DISABLE_DEPRECATION_WARNINGS
+    frame->pkt_pts = pkt->pts;
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
+    frame->pts     = pkt->pts;
+
+    for (i = 0; i < FF_ARRAY_ELEMS(sd); i++) {
+        int size;
+        uint8_t *packet_sd = av_packet_get_side_data(pkt, sd[i].packet, &size);
+        if (packet_sd) {
+            AVFrameSideData *frame_sd = av_frame_new_side_data(frame,
+                                                               sd[i].frame,
+                                                               size);
+            if (!frame_sd)
+                return AVERROR(ENOMEM);
+
+            memcpy(frame_sd->data, packet_sd, size);
+        }
+    }
+
+    return 0;
+}
+
+int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
+{
+    const AVHWAccel *hwaccel = avctx->hwaccel;
+    int override_dimensions = 1;
+    int ret;
+
+    switch (avctx->codec_type) {
+    case AVMEDIA_TYPE_VIDEO:
+        if (frame->width <= 0 || frame->height <= 0) {
+            frame->width  = FFMAX(avctx->width, avctx->coded_width);
+            frame->height = FFMAX(avctx->height, avctx->coded_height);
+            override_dimensions = 0;
+        }
+        if (frame->format < 0)
+            frame->format              = avctx->pix_fmt;
+        if (!frame->sample_aspect_ratio.num)
+            frame->sample_aspect_ratio = avctx->sample_aspect_ratio;
+
+        if (av_image_check_sar(frame->width, frame->height,
+                               frame->sample_aspect_ratio) < 0) {
+            av_log(avctx, AV_LOG_WARNING, "ignoring invalid SAR: %u/%u\n",
+                   frame->sample_aspect_ratio.num,
+                   frame->sample_aspect_ratio.den);
+            frame->sample_aspect_ratio = (AVRational){ 0, 1 };
+        }
+
+        if ((ret = av_image_check_size(avctx->width, avctx->height, 0, avctx)) < 0)
+            return ret;
+        break;
+    case AVMEDIA_TYPE_AUDIO:
+        if (!frame->sample_rate)
+            frame->sample_rate    = avctx->sample_rate;
+        if (frame->format < 0)
+            frame->format         = avctx->sample_fmt;
+        if (!frame->channel_layout) {
+            if (avctx->channel_layout) {
+                 if (av_get_channel_layout_nb_channels(avctx->channel_layout) !=
+                     avctx->channels) {
+                     av_log(avctx, AV_LOG_ERROR, "Inconsistent channel "
+                            "configuration.\n");
+                     return AVERROR(EINVAL);
+                 }
+
+                frame->channel_layout = avctx->channel_layout;
+            } else {
+                if (avctx->channels > FF_SANE_NB_CHANNELS) {
+                    av_log(avctx, AV_LOG_ERROR, "Too many channels: %d.\n",
+                           avctx->channels);
+                    return AVERROR(ENOSYS);
+                }
+
+                frame->channel_layout = av_get_default_channel_layout(avctx->channels);
+                if (!frame->channel_layout)
+                    frame->channel_layout = (1ULL << avctx->channels) - 1;
+            }
+        }
+        break;
+    default: return AVERROR(EINVAL);
+    }
+
+    ret = ff_decode_frame_props(avctx, frame);
+    if (ret < 0)
+        return ret;
+
+    if (hwaccel) {
+        if (hwaccel->alloc_frame) {
+            ret = hwaccel->alloc_frame(avctx, frame);
+            goto end;
+        }
+    } else
+        avctx->sw_pix_fmt = avctx->pix_fmt;
+
+    ret = avctx->get_buffer2(avctx, frame, flags);
+
+end:
+    if (avctx->codec_type == AVMEDIA_TYPE_VIDEO && !override_dimensions) {
+        frame->width  = avctx->width;
+        frame->height = avctx->height;
+    }
+
+    return ret;
+}
+
+int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame)
+{
+    AVFrame *tmp;
+    int ret;
+
+    av_assert0(avctx->codec_type == AVMEDIA_TYPE_VIDEO);
+
+    if (!frame->data[0])
+        return ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF);
+
+    if (av_frame_is_writable(frame))
+        return ff_decode_frame_props(avctx, frame);
+
+    tmp = av_frame_alloc();
+    if (!tmp)
+        return AVERROR(ENOMEM);
+
+    av_frame_move_ref(tmp, frame);
+
+    ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF);
+    if (ret < 0) {
+        av_frame_free(&tmp);
+        return ret;
+    }
+
+    av_frame_copy(frame, tmp);
+    av_frame_free(&tmp);
+
+    return 0;
+}
+
+void avcodec_flush_buffers(AVCodecContext *avctx)
+{
+    avctx->internal->draining      = 0;
+    avctx->internal->draining_done = 0;
+    av_frame_unref(avctx->internal->buffer_frame);
+    av_packet_unref(avctx->internal->buffer_pkt);
+    avctx->internal->buffer_pkt_valid = 0;
+
+    if (HAVE_THREADS && avctx->active_thread_type & FF_THREAD_FRAME)
+        ff_thread_flush(avctx);
+    else if (avctx->codec->flush)
+        avctx->codec->flush(avctx);
+
+    if (!avctx->refcounted_frames)
+        av_frame_unref(avctx->internal->to_free);
+}
diff --git a/libavcodec/utils.c b/libavcodec/utils.c
index d8ba1d59c9..0b44bb6464 100644
--- a/libavcodec/utils.c
+++ b/libavcodec/utils.c
@@ -335,373 +335,6 @@ int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
     return ret;
 }
 
-static int update_frame_pool(AVCodecContext *avctx, AVFrame *frame)
-{
-    FramePool *pool = avctx->internal->pool;
-    int i, ret;
-
-    switch (avctx->codec_type) {
-    case AVMEDIA_TYPE_VIDEO: {
-        uint8_t *data[4];
-        int linesize[4];
-        int size[4] = { 0 };
-        int w = frame->width;
-        int h = frame->height;
-        int tmpsize, unaligned;
-
-        if (pool->format == frame->format &&
-            pool->width == frame->width && pool->height == frame->height)
-            return 0;
-
-        avcodec_align_dimensions2(avctx, &w, &h, pool->stride_align);
-
-        do {
-            // NOTE: do not align linesizes individually, this breaks e.g. assumptions
-            // that linesize[0] == 2*linesize[1] in the MPEG-encoder for 4:2:2
-            av_image_fill_linesizes(linesize, avctx->pix_fmt, w);
-            // increase alignment of w for next try (rhs gives the lowest bit set in w)
-            w += w & ~(w - 1);
-
-            unaligned = 0;
-            for (i = 0; i < 4; i++)
-                unaligned |= linesize[i] % pool->stride_align[i];
-        } while (unaligned);
-
-        tmpsize = av_image_fill_pointers(data, avctx->pix_fmt, h,
-                                         NULL, linesize);
-        if (tmpsize < 0)
-            return -1;
-
-        for (i = 0; i < 3 && data[i + 1]; i++)
-            size[i] = data[i + 1] - data[i];
-        size[i] = tmpsize - (data[i] - data[0]);
-
-        for (i = 0; i < 4; i++) {
-            av_buffer_pool_uninit(&pool->pools[i]);
-            pool->linesize[i] = linesize[i];
-            if (size[i]) {
-                pool->pools[i] = av_buffer_pool_init(size[i] + 16, NULL);
-                if (!pool->pools[i]) {
-                    ret = AVERROR(ENOMEM);
-                    goto fail;
-                }
-            }
-        }
-        pool->format = frame->format;
-        pool->width  = frame->width;
-        pool->height = frame->height;
-
-        break;
-        }
-    case AVMEDIA_TYPE_AUDIO: {
-        int ch     = av_get_channel_layout_nb_channels(frame->channel_layout);
-        int planar = av_sample_fmt_is_planar(frame->format);
-        int planes = planar ? ch : 1;
-
-        if (pool->format == frame->format && pool->planes == planes &&
-            pool->channels == ch && frame->nb_samples == pool->samples)
-            return 0;
-
-        av_buffer_pool_uninit(&pool->pools[0]);
-        ret = av_samples_get_buffer_size(&pool->linesize[0], ch,
-                                         frame->nb_samples, frame->format, 0);
-        if (ret < 0)
-            goto fail;
-
-        pool->pools[0] = av_buffer_pool_init(pool->linesize[0], NULL);
-        if (!pool->pools[0]) {
-            ret = AVERROR(ENOMEM);
-            goto fail;
-        }
-
-        pool->format     = frame->format;
-        pool->planes     = planes;
-        pool->channels   = ch;
-        pool->samples = frame->nb_samples;
-        break;
-        }
-    default: av_assert0(0);
-    }
-    return 0;
-fail:
-    for (i = 0; i < 4; i++)
-        av_buffer_pool_uninit(&pool->pools[i]);
-    pool->format = -1;
-    pool->planes = pool->channels = pool->samples = 0;
-    pool->width  = pool->height = 0;
-    return ret;
-}
-
-static int audio_get_buffer(AVCodecContext *avctx, AVFrame *frame)
-{
-    FramePool *pool = avctx->internal->pool;
-    int planes = pool->planes;
-    int i;
-
-    frame->linesize[0] = pool->linesize[0];
-
-    if (planes > AV_NUM_DATA_POINTERS) {
-        frame->extended_data = av_mallocz(planes * sizeof(*frame->extended_data));
-        frame->nb_extended_buf = planes - AV_NUM_DATA_POINTERS;
-        frame->extended_buf  = av_mallocz(frame->nb_extended_buf *
-                                          sizeof(*frame->extended_buf));
-        if (!frame->extended_data || !frame->extended_buf) {
-            av_freep(&frame->extended_data);
-            av_freep(&frame->extended_buf);
-            return AVERROR(ENOMEM);
-        }
-    } else
-        frame->extended_data = frame->data;
-
-    for (i = 0; i < FFMIN(planes, AV_NUM_DATA_POINTERS); i++) {
-        frame->buf[i] = av_buffer_pool_get(pool->pools[0]);
-        if (!frame->buf[i])
-            goto fail;
-        frame->extended_data[i] = frame->data[i] = frame->buf[i]->data;
-    }
-    for (i = 0; i < frame->nb_extended_buf; i++) {
-        frame->extended_buf[i] = av_buffer_pool_get(pool->pools[0]);
-        if (!frame->extended_buf[i])
-            goto fail;
-        frame->extended_data[i + AV_NUM_DATA_POINTERS] = frame->extended_buf[i]->data;
-    }
-
-    if (avctx->debug & FF_DEBUG_BUFFERS)
-        av_log(avctx, AV_LOG_DEBUG, "default_get_buffer called on frame %p", frame);
-
-    return 0;
-fail:
-    av_frame_unref(frame);
-    return AVERROR(ENOMEM);
-}
-
-static int video_get_buffer(AVCodecContext *s, AVFrame *pic)
-{
-    FramePool *pool = s->internal->pool;
-    int i;
-
-    if (pic->data[0]) {
-        av_log(s, AV_LOG_ERROR, "pic->data[0]!=NULL in avcodec_default_get_buffer\n");
-        return -1;
-    }
-
-    memset(pic->data, 0, sizeof(pic->data));
-    pic->extended_data = pic->data;
-
-    for (i = 0; i < 4 && pool->pools[i]; i++) {
-        pic->linesize[i] = pool->linesize[i];
-
-        pic->buf[i] = av_buffer_pool_get(pool->pools[i]);
-        if (!pic->buf[i])
-            goto fail;
-
-        pic->data[i] = pic->buf[i]->data;
-    }
-    for (; i < AV_NUM_DATA_POINTERS; i++) {
-        pic->data[i] = NULL;
-        pic->linesize[i] = 0;
-    }
-    if (pic->data[1] && !pic->data[2])
-        avpriv_set_systematic_pal2((uint32_t *)pic->data[1], s->pix_fmt);
-
-    if (s->debug & FF_DEBUG_BUFFERS)
-        av_log(s, AV_LOG_DEBUG, "default_get_buffer called on pic %p\n", pic);
-
-    return 0;
-fail:
-    av_frame_unref(pic);
-    return AVERROR(ENOMEM);
-}
-
-int avcodec_default_get_buffer2(AVCodecContext *avctx, AVFrame *frame, int flags)
-{
-    int ret;
-
-    if (avctx->hw_frames_ctx)
-        return av_hwframe_get_buffer(avctx->hw_frames_ctx, frame, 0);
-
-    if ((ret = update_frame_pool(avctx, frame)) < 0)
-        return ret;
-
-    switch (avctx->codec_type) {
-    case AVMEDIA_TYPE_VIDEO:
-        return video_get_buffer(avctx, frame);
-    case AVMEDIA_TYPE_AUDIO:
-        return audio_get_buffer(avctx, frame);
-    default:
-        return -1;
-    }
-}
-
-int ff_decode_frame_props(AVCodecContext *avctx, AVFrame *frame)
-{
-    AVPacket *pkt = avctx->internal->pkt;
-    int i;
-    struct {
-        enum AVPacketSideDataType packet;
-        enum AVFrameSideDataType frame;
-    } sd[] = {
-        { AV_PKT_DATA_REPLAYGAIN ,   AV_FRAME_DATA_REPLAYGAIN },
-        { AV_PKT_DATA_DISPLAYMATRIX, AV_FRAME_DATA_DISPLAYMATRIX },
-        { AV_PKT_DATA_STEREO3D,      AV_FRAME_DATA_STEREO3D },
-        { AV_PKT_DATA_AUDIO_SERVICE_TYPE, AV_FRAME_DATA_AUDIO_SERVICE_TYPE },
-    };
-
-    frame->color_primaries = avctx->color_primaries;
-    frame->color_trc       = avctx->color_trc;
-    frame->colorspace      = avctx->colorspace;
-    frame->color_range     = avctx->color_range;
-    frame->chroma_location = avctx->chroma_sample_location;
-
-    frame->reordered_opaque = avctx->reordered_opaque;
-    if (!pkt) {
-#if FF_API_PKT_PTS
-FF_DISABLE_DEPRECATION_WARNINGS
-        frame->pkt_pts = AV_NOPTS_VALUE;
-FF_ENABLE_DEPRECATION_WARNINGS
-#endif
-        frame->pts     = AV_NOPTS_VALUE;
-        return 0;
-    }
-
-#if FF_API_PKT_PTS
-FF_DISABLE_DEPRECATION_WARNINGS
-    frame->pkt_pts = pkt->pts;
-FF_ENABLE_DEPRECATION_WARNINGS
-#endif
-    frame->pts     = pkt->pts;
-
-    for (i = 0; i < FF_ARRAY_ELEMS(sd); i++) {
-        int size;
-        uint8_t *packet_sd = av_packet_get_side_data(pkt, sd[i].packet, &size);
-        if (packet_sd) {
-            AVFrameSideData *frame_sd = av_frame_new_side_data(frame,
-                                                               sd[i].frame,
-                                                               size);
-            if (!frame_sd)
-                return AVERROR(ENOMEM);
-
-            memcpy(frame_sd->data, packet_sd, size);
-        }
-    }
-
-    return 0;
-}
-
-int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
-{
-    const AVHWAccel *hwaccel = avctx->hwaccel;
-    int override_dimensions = 1;
-    int ret;
-
-    switch (avctx->codec_type) {
-    case AVMEDIA_TYPE_VIDEO:
-        if (frame->width <= 0 || frame->height <= 0) {
-            frame->width  = FFMAX(avctx->width, avctx->coded_width);
-            frame->height = FFMAX(avctx->height, avctx->coded_height);
-            override_dimensions = 0;
-        }
-        if (frame->format < 0)
-            frame->format              = avctx->pix_fmt;
-        if (!frame->sample_aspect_ratio.num)
-            frame->sample_aspect_ratio = avctx->sample_aspect_ratio;
-
-        if (av_image_check_sar(frame->width, frame->height,
-                               frame->sample_aspect_ratio) < 0) {
-            av_log(avctx, AV_LOG_WARNING, "ignoring invalid SAR: %u/%u\n",
-                   frame->sample_aspect_ratio.num,
-                   frame->sample_aspect_ratio.den);
-            frame->sample_aspect_ratio = (AVRational){ 0, 1 };
-        }
-
-        if ((ret = av_image_check_size(avctx->width, avctx->height, 0, avctx)) < 0)
-            return ret;
-        break;
-    case AVMEDIA_TYPE_AUDIO:
-        if (!frame->sample_rate)
-            frame->sample_rate    = avctx->sample_rate;
-        if (frame->format < 0)
-            frame->format         = avctx->sample_fmt;
-        if (!frame->channel_layout) {
-            if (avctx->channel_layout) {
-                 if (av_get_channel_layout_nb_channels(avctx->channel_layout) !=
-                     avctx->channels) {
-                     av_log(avctx, AV_LOG_ERROR, "Inconsistent channel "
-                            "configuration.\n");
-                     return AVERROR(EINVAL);
-                 }
-
-                frame->channel_layout = avctx->channel_layout;
-            } else {
-                if (avctx->channels > FF_SANE_NB_CHANNELS) {
-                    av_log(avctx, AV_LOG_ERROR, "Too many channels: %d.\n",
-                           avctx->channels);
-                    return AVERROR(ENOSYS);
-                }
-
-                frame->channel_layout = av_get_default_channel_layout(avctx->channels);
-                if (!frame->channel_layout)
-                    frame->channel_layout = (1ULL << avctx->channels) - 1;
-            }
-        }
-        break;
-    default: return AVERROR(EINVAL);
-    }
-
-    ret = ff_decode_frame_props(avctx, frame);
-    if (ret < 0)
-        return ret;
-
-    if (hwaccel) {
-        if (hwaccel->alloc_frame) {
-            ret = hwaccel->alloc_frame(avctx, frame);
-            goto end;
-        }
-    } else
-        avctx->sw_pix_fmt = avctx->pix_fmt;
-
-    ret = avctx->get_buffer2(avctx, frame, flags);
-
-end:
-    if (avctx->codec_type == AVMEDIA_TYPE_VIDEO && !override_dimensions) {
-        frame->width  = avctx->width;
-        frame->height = avctx->height;
-    }
-
-    return ret;
-}
-
-int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame)
-{
-    AVFrame *tmp;
-    int ret;
-
-    av_assert0(avctx->codec_type == AVMEDIA_TYPE_VIDEO);
-
-    if (!frame->data[0])
-        return ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF);
-
-    if (av_frame_is_writable(frame))
-        return ff_decode_frame_props(avctx, frame);
-
-    tmp = av_frame_alloc();
-    if (!tmp)
-        return AVERROR(ENOMEM);
-
-    av_frame_move_ref(tmp, frame);
-
-    ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF);
-    if (ret < 0) {
-        av_frame_free(&tmp);
-        return ret;
-    }
-
-    av_frame_copy(frame, tmp);
-    av_frame_free(&tmp);
-
-    return 0;
-}
-
 int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2), void *arg, int *ret, int count, int size)
 {
     int i;
@@ -726,129 +359,6 @@ int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2,
     return 0;
 }
 
-static int is_hwaccel_pix_fmt(enum AVPixelFormat pix_fmt)
-{
-    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
-    return desc->flags & AV_PIX_FMT_FLAG_HWACCEL;
-}
-
-enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
-{
-    while (*fmt != AV_PIX_FMT_NONE && is_hwaccel_pix_fmt(*fmt))
-        ++fmt;
-    return fmt[0];
-}
-
-static AVHWAccel *find_hwaccel(enum AVCodecID codec_id,
-                               enum AVPixelFormat pix_fmt)
-{
-    AVHWAccel *hwaccel = NULL;
-
-    while ((hwaccel = av_hwaccel_next(hwaccel)))
-        if (hwaccel->id == codec_id
-            && hwaccel->pix_fmt == pix_fmt)
-            return hwaccel;
-    return NULL;
-}
-
-static int setup_hwaccel(AVCodecContext *avctx,
-                         const enum AVPixelFormat fmt,
-                         const char *name)
-{
-    AVHWAccel *hwa = find_hwaccel(avctx->codec_id, fmt);
-    int ret        = 0;
-
-    if (!hwa) {
-        av_log(avctx, AV_LOG_ERROR,
-               "Could not find an AVHWAccel for the pixel format: %s",
-               name);
-        return AVERROR(ENOENT);
-    }
-
-    if (hwa->priv_data_size) {
-        avctx->internal->hwaccel_priv_data = av_mallocz(hwa->priv_data_size);
-        if (!avctx->internal->hwaccel_priv_data)
-            return AVERROR(ENOMEM);
-    }
-
-    if (hwa->init) {
-        ret = hwa->init(avctx);
-        if (ret < 0) {
-            av_freep(&avctx->internal->hwaccel_priv_data);
-            return ret;
-        }
-    }
-
-    avctx->hwaccel = hwa;
-
-    return 0;
-}
-
-int ff_get_format(AVCodecContext *avctx, const enum AVPixelFormat *fmt)
-{
-    const AVPixFmtDescriptor *desc;
-    enum AVPixelFormat *choices;
-    enum AVPixelFormat ret;
-    unsigned n = 0;
-
-    while (fmt[n] != AV_PIX_FMT_NONE)
-        ++n;
-
-    av_assert0(n >= 1);
-    avctx->sw_pix_fmt = fmt[n - 1];
-    av_assert2(!is_hwaccel_pix_fmt(avctx->sw_pix_fmt));
-
-    choices = av_malloc_array(n + 1, sizeof(*choices));
-    if (!choices)
-        return AV_PIX_FMT_NONE;
-
-    memcpy(choices, fmt, (n + 1) * sizeof(*choices));
-
-    for (;;) {
-        if (avctx->hwaccel && avctx->hwaccel->uninit)
-            avctx->hwaccel->uninit(avctx);
-        av_freep(&avctx->internal->hwaccel_priv_data);
-        avctx->hwaccel = NULL;
-
-        av_buffer_unref(&avctx->hw_frames_ctx);
-
-        ret = avctx->get_format(avctx, choices);
-
-        desc = av_pix_fmt_desc_get(ret);
-        if (!desc) {
-            ret = AV_PIX_FMT_NONE;
-            break;
-        }
-
-        if (!(desc->flags & AV_PIX_FMT_FLAG_HWACCEL))
-            break;
-
-        if (avctx->hw_frames_ctx) {
-            AVHWFramesContext *hw_frames_ctx = (AVHWFramesContext*)avctx->hw_frames_ctx->data;
-            if (hw_frames_ctx->format != ret) {
-                av_log(avctx, AV_LOG_ERROR, "Format returned from get_buffer() "
-                       "does not match the format of provided AVHWFramesContext\n");
-                ret = AV_PIX_FMT_NONE;
-                break;
-            }
-        }
-
-        if (!setup_hwaccel(avctx, ret, desc->name))
-            break;
-
-        /* Remove failed hwaccel from choices */
-        for (n = 0; choices[n] != ret; n++)
-            av_assert0(choices[n] != AV_PIX_FMT_NONE);
-
-        do
-            choices[n] = choices[n + 1];
-        while (choices[n++] != AV_PIX_FMT_NONE);
-    }
-
-    av_freep(&choices);
-    return ret;
-}
-
 int attribute_align_arg avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
 {
     int ret = 0;
@@ -1210,244 +720,6 @@ FF_ENABLE_DEPRECATION_WARNINGS
     goto end;
 }
 
-static int apply_param_change(AVCodecContext *avctx, AVPacket *avpkt)
-{
-    int size = 0, ret;
-    const uint8_t *data;
-    uint32_t flags;
-
-    data = av_packet_get_side_data(avpkt, AV_PKT_DATA_PARAM_CHANGE, &size);
-    if (!data)
-        return 0;
-
-    if (!(avctx->codec->capabilities & AV_CODEC_CAP_PARAM_CHANGE)) {
-        av_log(avctx, AV_LOG_ERROR, "This decoder does not support parameter "
-               "changes, but PARAM_CHANGE side data was sent to it.\n");
-        ret = AVERROR(EINVAL);
-        goto fail2;
-    }
-
-    if (size < 4)
-        goto fail;
-
-    flags = bytestream_get_le32(&data);
-    size -= 4;
-
-    if (flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT) {
-        if (size < 4)
-            goto fail;
-        avctx->channels = bytestream_get_le32(&data);
-        size -= 4;
-    }
-    if (flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT) {
-        if (size < 8)
-            goto fail;
-        avctx->channel_layout = bytestream_get_le64(&data);
-        size -= 8;
-    }
-    if (flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE) {
-        if (size < 4)
-            goto fail;
-        avctx->sample_rate = bytestream_get_le32(&data);
-        size -= 4;
-    }
-    if (flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS) {
-        if (size < 8)
-            goto fail;
-        avctx->width  = bytestream_get_le32(&data);
-        avctx->height = bytestream_get_le32(&data);
-        size -= 8;
-        ret = ff_set_dimensions(avctx, avctx->width, avctx->height);
-        if (ret < 0)
-            goto fail2;
-    }
-
-    return 0;
-fail:
-    av_log(avctx, AV_LOG_ERROR, "PARAM_CHANGE side data too small.\n");
-    ret = AVERROR_INVALIDDATA;
-fail2:
-    if (ret < 0) {
-        av_log(avctx, AV_LOG_ERROR, "Error applying parameter changes.\n");
-        if (avctx->err_recognition & AV_EF_EXPLODE)
-            return ret;
-    }
-    return 0;
-}
-
-static int unrefcount_frame(AVCodecInternal *avci, AVFrame *frame)
-{
-    int ret;
-
-    /* move the original frame to our backup */
-    av_frame_unref(avci->to_free);
-    av_frame_move_ref(avci->to_free, frame);
-
-    /* now copy everything except the AVBufferRefs back
-     * note that we make a COPY of the side data, so calling av_frame_free() on
-     * the caller's frame will work properly */
-    ret = av_frame_copy_props(frame, avci->to_free);
-    if (ret < 0)
-        return ret;
-
-    memcpy(frame->data,     avci->to_free->data,     sizeof(frame->data));
-    memcpy(frame->linesize, avci->to_free->linesize, sizeof(frame->linesize));
-    if (avci->to_free->extended_data != avci->to_free->data) {
-        int planes = av_get_channel_layout_nb_channels(avci->to_free->channel_layout);
-        int size   = planes * sizeof(*frame->extended_data);
-
-        if (!size) {
-            av_frame_unref(frame);
-            return AVERROR_BUG;
-        }
-
-        frame->extended_data = av_malloc(size);
-        if (!frame->extended_data) {
-            av_frame_unref(frame);
-            return AVERROR(ENOMEM);
-        }
-        memcpy(frame->extended_data, avci->to_free->extended_data,
-               size);
-    } else
-        frame->extended_data = frame->data;
-
-    frame->format         = avci->to_free->format;
-    frame->width          = avci->to_free->width;
-    frame->height         = avci->to_free->height;
-    frame->channel_layout = avci->to_free->channel_layout;
-    frame->nb_samples     = avci->to_free->nb_samples;
-
-    return 0;
-}
-
-int attribute_align_arg avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
-                                              int *got_picture_ptr,
-                                              AVPacket *avpkt)
-{
-    AVCodecInternal *avci = avctx->internal;
-    int ret;
-
-    *got_picture_ptr = 0;
-    if ((avctx->coded_width || avctx->coded_height) && av_image_check_size(avctx->coded_width, avctx->coded_height, 0, avctx))
-        return -1;
-
-    if (!avctx->codec->decode) {
-        av_log(avctx, AV_LOG_ERROR, "This decoder requires using the avcodec_send_packet() API.\n");
-        return AVERROR(ENOSYS);
-    }
-
-    avctx->internal->pkt = avpkt;
-    ret = apply_param_change(avctx, avpkt);
-    if (ret < 0)
-        return ret;
-
-    av_frame_unref(picture);
-
-    if ((avctx->codec->capabilities & AV_CODEC_CAP_DELAY) || avpkt->size ||
-        (avctx->active_thread_type & FF_THREAD_FRAME)) {
-        if (HAVE_THREADS && avctx->active_thread_type & FF_THREAD_FRAME)
-            ret = ff_thread_decode_frame(avctx, picture, got_picture_ptr,
-                                         avpkt);
-        else {
-            ret = avctx->codec->decode(avctx, picture, got_picture_ptr,
-                                       avpkt);
-            if (!(avctx->codec->caps_internal & FF_CODEC_CAP_SETS_PKT_DTS))
-                picture->pkt_dts = avpkt->dts;
-            /* get_buffer is supposed to set frame parameters */
-            if (!(avctx->codec->capabilities & AV_CODEC_CAP_DR1)) {
-                picture->sample_aspect_ratio = avctx->sample_aspect_ratio;
-                picture->width               = avctx->width;
-                picture->height              = avctx->height;
-                picture->format              = avctx->pix_fmt;
-            }
-        }
-
-        emms_c(); //needed to avoid an emms_c() call before every return;
-
-        if (*got_picture_ptr) {
-            if (!avctx->refcounted_frames) {
-                int err = unrefcount_frame(avci, picture);
-                if (err < 0)
-                    return err;
-            }
-
-            avctx->frame_number++;
-        } else
-            av_frame_unref(picture);
-    } else
-        ret = 0;
-
-#if FF_API_AVCTX_TIMEBASE
-    if (avctx->framerate.num > 0 && avctx->framerate.den > 0)
-        avctx->time_base = av_inv_q(avctx->framerate);
-#endif
-
-    return ret;
-}
-
-int attribute_align_arg avcodec_decode_audio4(AVCodecContext *avctx,
-                                              AVFrame *frame,
-                                              int *got_frame_ptr,
-                                              AVPacket *avpkt)
-{
-    AVCodecInternal *avci = avctx->internal;
-    int ret = 0;
-
-    *got_frame_ptr = 0;
-
-    if (!avctx->codec->decode) {
-        av_log(avctx, AV_LOG_ERROR, "This decoder requires using the avcodec_send_packet() API.\n");
-        return AVERROR(ENOSYS);
-    }
-
-    avctx->internal->pkt = avpkt;
-
-    if (!avpkt->data && avpkt->size) {
-        av_log(avctx, AV_LOG_ERROR, "invalid packet: NULL data, size != 0\n");
-        return AVERROR(EINVAL);
-    }
-
-    ret = apply_param_change(avctx, avpkt);
-    if (ret < 0)
-        return ret;
-
-    av_frame_unref(frame);
-
-    if ((avctx->codec->capabilities & AV_CODEC_CAP_DELAY) || avpkt->size) {
-        ret = avctx->codec->decode(avctx, frame, got_frame_ptr, avpkt);
-        if (ret >= 0 && *got_frame_ptr) {
-            avctx->frame_number++;
-            frame->pkt_dts = avpkt->dts;
-            if (frame->format == AV_SAMPLE_FMT_NONE)
-                frame->format = avctx->sample_fmt;
-
-            if (!avctx->refcounted_frames) {
-                int err = unrefcount_frame(avci, frame);
-                if (err < 0)
-                    return err;
-            }
-        } else
-            av_frame_unref(frame);
-    }
-
-
-    return ret;
-}
-
-int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
-                             int *got_sub_ptr,
-                             AVPacket *avpkt)
-{
-    int ret;
-
-    avctx->internal->pkt = avpkt;
-    *got_sub_ptr = 0;
-    ret = avctx->codec->decode(avctx, sub, got_sub_ptr, avpkt);
-    if (*got_sub_ptr)
-        avctx->frame_number++;
-    return ret;
-}
-
 void avsubtitle_free(AVSubtitle *sub)
 {
     int i;
@@ -1467,150 +739,6 @@ void avsubtitle_free(AVSubtitle *sub)
     memset(sub, 0, sizeof(AVSubtitle));
 }
 
-static int do_decode(AVCodecContext *avctx, AVPacket *pkt)
-{
-    int got_frame;
-    int ret;
-
-    av_assert0(!avctx->internal->buffer_frame->buf[0]);
-
-    if (!pkt)
-        pkt = avctx->internal->buffer_pkt;
-
-    // This is the lesser evil. The field is for compatibility with legacy users
-    // of the legacy API, and users using the new API should not be forced to
-    // even know about this field.
-    avctx->refcounted_frames = 1;
-
-    // Some codecs (at least wma lossless) will crash when feeding drain packets
-    // after EOF was signaled.
-    if (avctx->internal->draining_done)
-        return AVERROR_EOF;
-
-    if (avctx->codec_type == AVMEDIA_TYPE_VIDEO) {
-        ret = avcodec_decode_video2(avctx, avctx->internal->buffer_frame,
-                                    &got_frame, pkt);
-        if (ret >= 0)
-            ret = pkt->size;
-    } else if (avctx->codec_type == AVMEDIA_TYPE_AUDIO) {
-        ret = avcodec_decode_audio4(avctx, avctx->internal->buffer_frame,
-                                    &got_frame, pkt);
-    } else {
-        ret = AVERROR(EINVAL);
-    }
-
-    if (ret < 0)
-        return ret;
-
-    if (avctx->internal->draining && !got_frame)
-        avctx->internal->draining_done = 1;
-
-    if (ret >= pkt->size) {
-        av_packet_unref(avctx->internal->buffer_pkt);
-    } else {
-        int consumed = ret;
-
-        if (pkt != avctx->internal->buffer_pkt) {
-            av_packet_unref(avctx->internal->buffer_pkt);
-            if ((ret = av_packet_ref(avctx->internal->buffer_pkt, pkt)) < 0)
-                return ret;
-        }
-
-        avctx->internal->buffer_pkt->data += consumed;
-        avctx->internal->buffer_pkt->size -= consumed;
-        avctx->internal->buffer_pkt->pts   = AV_NOPTS_VALUE;
-        avctx->internal->buffer_pkt->dts   = AV_NOPTS_VALUE;
-    }
-
-    if (got_frame)
-        av_assert0(avctx->internal->buffer_frame->buf[0]);
-
-    return 0;
-}
-
-int attribute_align_arg avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
-{
-    int ret;
-
-    if (!avcodec_is_open(avctx) || !av_codec_is_decoder(avctx->codec))
-        return AVERROR(EINVAL);
-
-    if (avctx->internal->draining)
-        return AVERROR_EOF;
-
-    if (!avpkt || !avpkt->size) {
-        avctx->internal->draining = 1;
-        avpkt = NULL;
-
-        if (!(avctx->codec->capabilities & AV_CODEC_CAP_DELAY))
-            return 0;
-    }
-
-    if (avctx->codec->send_packet) {
-        if (avpkt) {
-            ret = apply_param_change(avctx, (AVPacket *)avpkt);
-            if (ret < 0)
-                return ret;
-        }
-        return avctx->codec->send_packet(avctx, avpkt);
-    }
-
-    // Emulation via old API. Assume avpkt is likely not refcounted, while
-    // decoder output is always refcounted, and avoid copying.
-
-    if (avctx->internal->buffer_pkt->size || avctx->internal->buffer_frame->buf[0])
-        return AVERROR(EAGAIN);
-
-    // The goal is decoding the first frame of the packet without using memcpy,
-    // because the common case is having only 1 frame per packet (especially
-    // with video, but audio too). In other cases, it can't be avoided, unless
-    // the user is feeding refcounted packets.
-    return do_decode(avctx, (AVPacket *)avpkt);
-}
-
-int attribute_align_arg avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
-{
-    int ret;
-
-    av_frame_unref(frame);
-
-    if (!avcodec_is_open(avctx) || !av_codec_is_decoder(avctx->codec))
-        return AVERROR(EINVAL);
-
-    if (avctx->codec->receive_frame) {
-        if (avctx->internal->draining && !(avctx->codec->capabilities & AV_CODEC_CAP_DELAY))
-            return AVERROR_EOF;
-        return avctx->codec->receive_frame(avctx, frame);
-    }
-
-    // Emulation via old API.
-
-    if (!avctx->internal->buffer_frame->buf[0]) {
-        if (!avctx->internal->buffer_pkt->size && !avctx->internal->draining)
-            return AVERROR(EAGAIN);
-
-        while (1) {
-            if ((ret = do_decode(avctx, avctx->internal->buffer_pkt)) < 0) {
-                av_packet_unref(avctx->internal->buffer_pkt);
-                return ret;
-            }
-            // Some audio decoders may consume partial data without returning
-            // a frame (fate-wmapro-2ch). There is no way to make the caller
-            // call avcodec_receive_frame() again without returning a frame,
-            // so try to decode more in these cases.
-            if (avctx->internal->buffer_frame->buf[0] ||
-                !avctx->internal->buffer_pkt->size)
-                break;
-        }
-    }
-
-    if (!avctx->internal->buffer_frame->buf[0])
-        return avctx->internal->draining ? AVERROR_EOF : AVERROR(EAGAIN);
-
-    av_frame_move_ref(frame, avctx->internal->buffer_frame);
-    return 0;
-}
-
 av_cold int avcodec_close(AVCodecContext *avctx)
 {
     int i;
@@ -1953,23 +1081,6 @@ const char *avcodec_license(void)
     return LICENSE_PREFIX LIBAV_LICENSE + sizeof(LICENSE_PREFIX) - 1;
 }
 
-void avcodec_flush_buffers(AVCodecContext *avctx)
-{
-    avctx->internal->draining      = 0;
-    avctx->internal->draining_done = 0;
-    av_frame_unref(avctx->internal->buffer_frame);
-    av_packet_unref(avctx->internal->buffer_pkt);
-    avctx->internal->buffer_pkt_valid = 0;
-
-    if (HAVE_THREADS && avctx->active_thread_type & FF_THREAD_FRAME)
-        ff_thread_flush(avctx);
-    else if (avctx->codec->flush)
-        avctx->codec->flush(avctx);
-
-    if (!avctx->refcounted_frames)
-        av_frame_unref(avctx->internal->to_free);
-}
-
 int av_get_exact_bits_per_sample(enum AVCodecID codec_id)
 {
     switch (codec_id) {