split ffm de/muxer

Originally committed as revision 13413 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 498 insertions, 0 deletions

diff --git a/libavformat/ffmdec.c b/libavformat/ffmdec.c
new file mode 100644
index 0000000000..706aa7d019
--- /dev/null
+++ b/libavformat/ffmdec.c
@@ -0,0 +1,498 @@
+/*
+ * FFM (ffserver live feed) demuxer
+ * Copyright (c) 2001 Fabrice Bellard.
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "avformat.h"
+#include "ffm.h"
+#include <unistd.h>
+
+static int64_t get_pts(AVFormatContext *s, offset_t pos);
+
+static int ffm_is_avail_data(AVFormatContext *s, int size)
+{
+    FFMContext *ffm = s->priv_data;
+    offset_t pos, avail_size;
+    int len;
+
+    len = ffm->packet_end - ffm->packet_ptr;
+    if (size <= len)
+        return 1;
+    pos = url_ftell(s->pb);
+    if (pos == ffm->write_index) {
+        /* exactly at the end of stream */
+        return 0;
+    } else if (pos < ffm->write_index) {
+        avail_size = ffm->write_index - pos;
+    } else {
+        avail_size = (ffm->file_size - pos) + (ffm->write_index - FFM_PACKET_SIZE);
+    }
+    avail_size = (avail_size / ffm->packet_size) * (ffm->packet_size - FFM_HEADER_SIZE) + len;
+    if (size <= avail_size)
+        return 1;
+    else
+        return 0;
+}
+
+/* first is true if we read the frame header */
+static int ffm_read_data(AVFormatContext *s,
+                         uint8_t *buf, int size, int first)
+{
+    FFMContext *ffm = s->priv_data;
+    ByteIOContext *pb = s->pb;
+    int len, fill_size, size1, frame_offset;
+
+    size1 = size;
+    while (size > 0) {
+    redo:
+        len = ffm->packet_end - ffm->packet_ptr;
+        if (len > size)
+            len = size;
+        if (len == 0) {
+            if (url_ftell(pb) == ffm->file_size)
+                url_fseek(pb, ffm->packet_size, SEEK_SET);
+    retry_read:
+            get_be16(pb); /* PACKET_ID */
+            fill_size = get_be16(pb);
+            ffm->pts = get_be64(pb);
+            ffm->first_frame_in_packet = 1;
+            frame_offset = get_be16(pb);
+            get_buffer(pb, ffm->packet, ffm->packet_size - FFM_HEADER_SIZE);
+            ffm->packet_end = ffm->packet + (ffm->packet_size - FFM_HEADER_SIZE - fill_size);
+            if (ffm->packet_end < ffm->packet)
+                return -1;
+            /* if first packet or resynchronization packet, we must
+               handle it specifically */
+            if (ffm->first_packet || (frame_offset & 0x8000)) {
+                if (!frame_offset) {
+                    /* This packet has no frame headers in it */
+                    if (url_ftell(pb) >= ffm->packet_size * 3) {
+                        url_fseek(pb, -ffm->packet_size * 2, SEEK_CUR);
+                        goto retry_read;
+                    }
+                    /* This is bad, we cannot find a valid frame header */
+                    return 0;
+                }
+                ffm->first_packet = 0;
+                if ((frame_offset & 0x7ffff) < FFM_HEADER_SIZE)
+                    return -1;
+                ffm->packet_ptr = ffm->packet + (frame_offset & 0x7fff) - FFM_HEADER_SIZE;
+                if (!first)
+                    break;
+            } else {
+                ffm->packet_ptr = ffm->packet;
+            }
+            goto redo;
+        }
+        memcpy(buf, ffm->packet_ptr, len);
+        buf += len;
+        ffm->packet_ptr += len;
+        size -= len;
+        first = 0;
+    }
+    return size1 - size;
+}
+
+
+static void adjust_write_index(AVFormatContext *s)
+{
+    FFMContext *ffm = s->priv_data;
+    ByteIOContext *pb = s->pb;
+    int64_t pts;
+    //offset_t orig_write_index = ffm->write_index;
+    offset_t pos_min, pos_max;
+    int64_t pts_start;
+    offset_t ptr = url_ftell(pb);
+
+
+    pos_min = 0;
+    pos_max = ffm->file_size - 2 * FFM_PACKET_SIZE;
+
+    pts_start = get_pts(s, pos_min);
+
+    pts = get_pts(s, pos_max);
+
+    if (pts - 100000 > pts_start)
+        goto end;
+
+    ffm->write_index = FFM_PACKET_SIZE;
+
+    pts_start = get_pts(s, pos_min);
+
+    pts = get_pts(s, pos_max);
+
+    if (pts - 100000 <= pts_start) {
+        while (1) {
+            offset_t newpos;
+            int64_t newpts;
+
+            newpos = ((pos_max + pos_min) / (2 * FFM_PACKET_SIZE)) * FFM_PACKET_SIZE;
+
+            if (newpos == pos_min)
+                break;
+
+            newpts = get_pts(s, newpos);
+
+            if (newpts - 100000 <= pts) {
+                pos_max = newpos;
+                pts = newpts;
+            } else {
+                pos_min = newpos;
+            }
+        }
+        ffm->write_index += pos_max;
+    }
+
+    //printf("Adjusted write index from %"PRId64" to %"PRId64": pts=%0.6f\n", orig_write_index, ffm->write_index, pts / 1000000.);
+    //printf("pts range %0.6f - %0.6f\n", get_pts(s, 0) / 1000000. , get_pts(s, ffm->file_size - 2 * FFM_PACKET_SIZE) / 1000000. );
+
+ end:
+    url_fseek(pb, ptr, SEEK_SET);
+}
+
+
+static int ffm_read_header(AVFormatContext *s, AVFormatParameters *ap)
+{
+    FFMContext *ffm = s->priv_data;
+    AVStream *st;
+    FFMStream *fst;
+    ByteIOContext *pb = s->pb;
+    AVCodecContext *codec;
+    int i, nb_streams;
+    uint32_t tag;
+
+    /* header */
+    tag = get_le32(pb);
+    if (tag != MKTAG('F', 'F', 'M', '1'))
+        goto fail;
+    ffm->packet_size = get_be32(pb);
+    if (ffm->packet_size != FFM_PACKET_SIZE)
+        goto fail;
+    ffm->write_index = get_be64(pb);
+    /* get also filesize */
+    if (!url_is_streamed(pb)) {
+        ffm->file_size = url_fsize(pb);
+        adjust_write_index(s);
+    } else {
+        ffm->file_size = (UINT64_C(1) << 63) - 1;
+    }
+
+    nb_streams = get_be32(pb);
+    get_be32(pb); /* total bitrate */
+    /* read each stream */
+    for(i=0;i<nb_streams;i++) {
+        char rc_eq_buf[128];
+
+        st = av_new_stream(s, 0);
+        if (!st)
+            goto fail;
+        fst = av_mallocz(sizeof(FFMStream));
+        if (!fst)
+            goto fail;
+        s->streams[i] = st;
+
+        av_set_pts_info(st, 64, 1, 1000000);
+
+        st->priv_data = fst;
+
+        codec = st->codec;
+        /* generic info */
+        codec->codec_id = get_be32(pb);
+        codec->codec_type = get_byte(pb); /* codec_type */
+        codec->bit_rate = get_be32(pb);
+        st->quality = get_be32(pb);
+        codec->flags = get_be32(pb);
+        codec->flags2 = get_be32(pb);
+        codec->debug = get_be32(pb);
+        /* specific info */
+        switch(codec->codec_type) {
+        case CODEC_TYPE_VIDEO:
+            codec->time_base.num = get_be32(pb);
+            codec->time_base.den = get_be32(pb);
+            codec->width = get_be16(pb);
+            codec->height = get_be16(pb);
+            codec->gop_size = get_be16(pb);
+            codec->pix_fmt = get_be32(pb);
+            codec->qmin = get_byte(pb);
+            codec->qmax = get_byte(pb);
+            codec->max_qdiff = get_byte(pb);
+            codec->qcompress = get_be16(pb) / 10000.0;
+            codec->qblur = get_be16(pb) / 10000.0;
+            codec->bit_rate_tolerance = get_be32(pb);
+            codec->rc_eq = av_strdup(get_strz(pb, rc_eq_buf, sizeof(rc_eq_buf)));
+            codec->rc_max_rate = get_be32(pb);
+            codec->rc_min_rate = get_be32(pb);
+            codec->rc_buffer_size = get_be32(pb);
+            codec->i_quant_factor = av_int2dbl(get_be64(pb));
+            codec->b_quant_factor = av_int2dbl(get_be64(pb));
+            codec->i_quant_offset = av_int2dbl(get_be64(pb));
+            codec->b_quant_offset = av_int2dbl(get_be64(pb));
+            codec->dct_algo = get_be32(pb);
+            codec->strict_std_compliance = get_be32(pb);
+            codec->max_b_frames = get_be32(pb);
+            codec->luma_elim_threshold = get_be32(pb);
+            codec->chroma_elim_threshold = get_be32(pb);
+            codec->mpeg_quant = get_be32(pb);
+            codec->intra_dc_precision = get_be32(pb);
+            codec->me_method = get_be32(pb);
+            codec->mb_decision = get_be32(pb);
+            codec->nsse_weight = get_be32(pb);
+            codec->frame_skip_cmp = get_be32(pb);
+            codec->rc_buffer_aggressivity = av_int2dbl(get_be64(pb));
+            codec->codec_tag = get_be32(pb);
+            break;
+        case CODEC_TYPE_AUDIO:
+            codec->sample_rate = get_be32(pb);
+            codec->channels = get_le16(pb);
+            codec->frame_size = get_le16(pb);
+            break;
+        default:
+            goto fail;
+        }
+
+    }
+
+    /* get until end of block reached */
+    while ((url_ftell(pb) % ffm->packet_size) != 0)
+        get_byte(pb);
+
+    /* init packet demux */
+    ffm->packet_ptr = ffm->packet;
+    ffm->packet_end = ffm->packet;
+    ffm->frame_offset = 0;
+    ffm->pts = 0;
+    ffm->read_state = READ_HEADER;
+    ffm->first_packet = 1;
+    return 0;
+ fail:
+    for(i=0;i<s->nb_streams;i++) {
+        st = s->streams[i];
+        if (st) {
+            av_freep(&st->priv_data);
+            av_free(st);
+        }
+    }
+    return -1;
+}
+
+/* return < 0 if eof */
+static int ffm_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    int size;
+    FFMContext *ffm = s->priv_data;
+    int duration;
+
+    switch(ffm->read_state) {
+    case READ_HEADER:
+        if (!ffm_is_avail_data(s, FRAME_HEADER_SIZE)) {
+            return AVERROR(EAGAIN);
+        }
+#if 0
+        printf("pos=%08"PRIx64" spos=%"PRIx64", write_index=%"PRIx64" size=%"PRIx64"\n",
+               url_ftell(s->pb), s->pb.pos, ffm->write_index, ffm->file_size);
+#endif
+        if (ffm_read_data(s, ffm->header, FRAME_HEADER_SIZE, 1) !=
+            FRAME_HEADER_SIZE)
+            return AVERROR(EAGAIN);
+#if 0
+        {
+            int i;
+            for(i=0;i<FRAME_HEADER_SIZE;i++)
+                printf("%02x ", ffm->header[i]);
+            printf("\n");
+        }
+#endif
+        ffm->read_state = READ_DATA;
+        /* fall thru */
+    case READ_DATA:
+        size = AV_RB24(ffm->header + 2);
+        if (!ffm_is_avail_data(s, size)) {
+            return AVERROR(EAGAIN);
+        }
+
+        duration = AV_RB24(ffm->header + 5);
+
+        av_new_packet(pkt, size);
+        pkt->stream_index = ffm->header[0];
+        if ((unsigned)pkt->stream_index >= s->nb_streams) {
+            av_log(s, AV_LOG_ERROR, "invalid stream index %d\n", pkt->stream_index);
+            av_free_packet(pkt);
+            ffm->read_state = READ_HEADER;
+            return AVERROR(EAGAIN);
+        }
+        pkt->pos = url_ftell(s->pb);
+        if (ffm->header[1] & FLAG_KEY_FRAME)
+            pkt->flags |= PKT_FLAG_KEY;
+
+        ffm->read_state = READ_HEADER;
+        if (ffm_read_data(s, pkt->data, size, 0) != size) {
+            /* bad case: desynchronized packet. we cancel all the packet loading */
+            av_free_packet(pkt);
+            return AVERROR(EAGAIN);
+        }
+        if (ffm->first_frame_in_packet)
+        {
+            pkt->pts = ffm->pts;
+            ffm->first_frame_in_packet = 0;
+        }
+        pkt->duration = duration;
+        break;
+    }
+    return 0;
+}
+
+//#define DEBUG_SEEK
+
+/* pos is between 0 and file_size - FFM_PACKET_SIZE. It is translated
+   by the write position inside this function */
+static void ffm_seek1(AVFormatContext *s, offset_t pos1)
+{
+    FFMContext *ffm = s->priv_data;
+    ByteIOContext *pb = s->pb;
+    offset_t pos;
+
+    pos = pos1 + ffm->write_index;
+    if (pos >= ffm->file_size)
+        pos -= (ffm->file_size - FFM_PACKET_SIZE);
+#ifdef DEBUG_SEEK
+    printf("seek to %"PRIx64" -> %"PRIx64"\n", pos1, pos);
+#endif
+    url_fseek(pb, pos, SEEK_SET);
+}
+
+static int64_t get_pts(AVFormatContext *s, offset_t pos)
+{
+    ByteIOContext *pb = s->pb;
+    int64_t pts;
+
+    ffm_seek1(s, pos);
+    url_fskip(pb, 4);
+    pts = get_be64(pb);
+#ifdef DEBUG_SEEK
+    printf("pts=%0.6f\n", pts / 1000000.0);
+#endif
+    return pts;
+}
+
+/* seek to a given time in the file. The file read pointer is
+   positioned at or before pts. XXX: the following code is quite
+   approximative */
+static int ffm_seek(AVFormatContext *s, int stream_index, int64_t wanted_pts, int flags)
+{
+    FFMContext *ffm = s->priv_data;
+    offset_t pos_min, pos_max, pos;
+    int64_t pts_min, pts_max, pts;
+    double pos1;
+
+#ifdef DEBUG_SEEK
+    printf("wanted_pts=%0.6f\n", wanted_pts / 1000000.0);
+#endif
+    /* find the position using linear interpolation (better than
+       dichotomy in typical cases) */
+    pos_min = 0;
+    pos_max = ffm->file_size - 2 * FFM_PACKET_SIZE;
+    while (pos_min <= pos_max) {
+        pts_min = get_pts(s, pos_min);
+        pts_max = get_pts(s, pos_max);
+        /* linear interpolation */
+        pos1 = (double)(pos_max - pos_min) * (double)(wanted_pts - pts_min) /
+            (double)(pts_max - pts_min);
+        pos = (((int64_t)pos1) / FFM_PACKET_SIZE) * FFM_PACKET_SIZE;
+        if (pos <= pos_min)
+            pos = pos_min;
+        else if (pos >= pos_max)
+            pos = pos_max;
+        pts = get_pts(s, pos);
+        /* check if we are lucky */
+        if (pts == wanted_pts) {
+            goto found;
+        } else if (pts > wanted_pts) {
+            pos_max = pos - FFM_PACKET_SIZE;
+        } else {
+            pos_min = pos + FFM_PACKET_SIZE;
+        }
+    }
+    pos = (flags & AVSEEK_FLAG_BACKWARD) ? pos_min : pos_max;
+    if (pos > 0)
+        pos -= FFM_PACKET_SIZE;
+ found:
+    ffm_seek1(s, pos);
+    return 0;
+}
+
+#ifdef CONFIG_FFSERVER
+offset_t ffm_read_write_index(int fd)
+{
+    uint8_t buf[8];
+
+    lseek(fd, 8, SEEK_SET);
+    read(fd, buf, 8);
+    return AV_RB64(buf);
+}
+
+void ffm_write_write_index(int fd, offset_t pos)
+{
+    uint8_t buf[8];
+    int i;
+
+    for(i=0;i<8;i++)
+        buf[i] = (pos >> (56 - i * 8)) & 0xff;
+    lseek(fd, 8, SEEK_SET);
+    write(fd, buf, 8);
+}
+
+void ffm_set_write_index(AVFormatContext *s, offset_t pos, offset_t file_size)
+{
+    FFMContext *ffm = s->priv_data;
+    ffm->write_index = pos;
+    ffm->file_size = file_size;
+}
+#endif // CONFIG_FFSERVER
+
+static int ffm_read_close(AVFormatContext *s)
+{
+    AVStream *st;
+    int i;
+
+    for(i=0;i<s->nb_streams;i++) {
+        st = s->streams[i];
+        av_freep(&st->priv_data);
+    }
+    return 0;
+}
+
+static int ffm_probe(AVProbeData *p)
+{
+    if (
+        p->buf[0] == 'F' && p->buf[1] == 'F' && p->buf[2] == 'M' &&
+        p->buf[3] == '1')
+        return AVPROBE_SCORE_MAX + 1;
+    return 0;
+}
+
+AVInputFormat ffm_demuxer = {
+    "ffm",
+    "ffm format",
+    sizeof(FFMContext),
+    ffm_probe,
+    ffm_read_header,
+    ffm_read_packet,
+    ffm_read_close,
+    ffm_seek,
+};