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-rw-r--r--libavcodec/gifdec.c438
1 files changed, 328 insertions, 110 deletions
diff --git a/libavcodec/gifdec.c b/libavcodec/gifdec.c
index cdb7f23fd4..78c8900628 100644
--- a/libavcodec/gifdec.c
+++ b/libavcodec/gifdec.c
@@ -2,122 +2,255 @@
* GIF decoder
* Copyright (c) 2003 Fabrice Bellard
* Copyright (c) 2006 Baptiste Coudurier
+ * Copyright (c) 2012 Vitaliy E Sugrobov
*
- * This file is part of Libav.
+ * This file is part of FFmpeg.
*
- * Libav is free software; you can redistribute it and/or
+ * 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.
*
- * Libav is distributed in the hope that it will be useful,
+ * 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 Libav; if not, write to the Free Software
+ * License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/imgutils.h"
+#include "libavutil/opt.h"
#include "avcodec.h"
#include "bytestream.h"
#include "internal.h"
#include "lzw.h"
+#include "gif.h"
-#define GCE_DISPOSAL_NONE 0
-#define GCE_DISPOSAL_INPLACE 1
-#define GCE_DISPOSAL_BACKGROUND 2
-#define GCE_DISPOSAL_RESTORE 3
+/* This value is intentionally set to "transparent white" color.
+ * It is much better to have white background instead of black
+ * when gif image converted to format which not support transparency.
+ */
+#define GIF_TRANSPARENT_COLOR 0x00ffffff
typedef struct GifState {
+ const AVClass *class;
+ AVFrame *frame;
int screen_width;
int screen_height;
+ int has_global_palette;
int bits_per_pixel;
+ uint32_t bg_color;
int background_color_index;
int transparent_color_index;
int color_resolution;
- uint32_t *image_palette;
+ /* intermediate buffer for storing color indices
+ * obtained from lzw-encoded data stream */
+ uint8_t *idx_line;
+ int idx_line_size;
/* after the frame is displayed, the disposal method is used */
+ int gce_prev_disposal;
int gce_disposal;
- /* delay during which the frame is shown */
- int gce_delay;
+ /* rectangle describing area that must be disposed */
+ int gce_l, gce_t, gce_w, gce_h;
+ /* depending on disposal method we store either part of the image
+ * drawn on the canvas or background color that
+ * should be used upon disposal */
+ uint32_t * stored_img;
+ int stored_img_size;
+ int stored_bg_color;
- /* LZW compatible decoder */
GetByteContext gb;
LZWState *lzw;
/* aux buffers */
- uint8_t global_palette[256 * 3];
- uint8_t local_palette[256 * 3];
+ uint32_t global_palette[256];
+ uint32_t local_palette[256];
- AVCodecContext* avctx;
+ AVCodecContext *avctx;
+ int keyframe;
+ int keyframe_ok;
+ int trans_color; /**< color value that is used instead of transparent color */
} GifState;
-static const uint8_t gif87a_sig[6] = "GIF87a";
-static const uint8_t gif89a_sig[6] = "GIF89a";
+static void gif_read_palette(GifState *s, uint32_t *pal, int nb)
+{
+ int i;
+
+ for (i = 0; i < nb; i++, pal++)
+ *pal = (0xffu << 24) | bytestream2_get_be24u(&s->gb);
+}
+
+static void gif_fill(AVFrame *picture, uint32_t color)
+{
+ uint32_t *p = (uint32_t *)picture->data[0];
+ uint32_t *p_end = p + (picture->linesize[0] / sizeof(uint32_t)) * picture->height;
+
+ for (; p < p_end; p++)
+ *p = color;
+}
+
+static void gif_fill_rect(AVFrame *picture, uint32_t color, int l, int t, int w, int h)
+{
+ const int linesize = picture->linesize[0] / sizeof(uint32_t);
+ const uint32_t *py = (uint32_t *)picture->data[0] + t * linesize;
+ const uint32_t *pr, *pb = py + h * linesize;
+ uint32_t *px;
+
+ for (; py < pb; py += linesize) {
+ px = (uint32_t *)py + l;
+ pr = px + w;
+
+ for (; px < pr; px++)
+ *px = color;
+ }
+}
+
+static void gif_copy_img_rect(const uint32_t *src, uint32_t *dst,
+ int linesize, int l, int t, int w, int h)
+{
+ const int y_start = t * linesize;
+ const uint32_t *src_px,
+ *src_py = src + y_start,
+ *dst_py = dst + y_start;
+ const uint32_t *src_pb = src_py + h * linesize;
+ uint32_t *dst_px;
+
+ for (; src_py < src_pb; src_py += linesize, dst_py += linesize) {
+ src_px = src_py + l;
+ dst_px = (uint32_t *)dst_py + l;
+
+ memcpy(dst_px, src_px, w * sizeof(uint32_t));
+ }
+}
static int gif_read_image(GifState *s, AVFrame *frame)
{
int left, top, width, height, bits_per_pixel, code_size, flags;
- int is_interleaved, has_local_palette, y, pass, y1, linesize, n, i;
- uint8_t *ptr, *spal, *palette, *ptr1;
-
- left = bytestream2_get_le16(&s->gb);
- top = bytestream2_get_le16(&s->gb);
- width = bytestream2_get_le16(&s->gb);
- height = bytestream2_get_le16(&s->gb);
- flags = bytestream2_get_byte(&s->gb);
+ int is_interleaved, has_local_palette, y, pass, y1, linesize, pal_size;
+ uint32_t *ptr, *pal, *px, *pr, *ptr1;
+ int ret;
+ uint8_t *idx;
+
+ /* At least 9 bytes of Image Descriptor. */
+ if (bytestream2_get_bytes_left(&s->gb) < 9)
+ return AVERROR_INVALIDDATA;
+
+ left = bytestream2_get_le16u(&s->gb);
+ top = bytestream2_get_le16u(&s->gb);
+ width = bytestream2_get_le16u(&s->gb);
+ height = bytestream2_get_le16u(&s->gb);
+ flags = bytestream2_get_byteu(&s->gb);
is_interleaved = flags & 0x40;
has_local_palette = flags & 0x80;
bits_per_pixel = (flags & 0x07) + 1;
- av_dlog(s->avctx, "gif: image x=%d y=%d w=%d h=%d\n", left, top, width, height);
+ av_dlog(s->avctx, "image x=%d y=%d w=%d h=%d\n", left, top, width, height);
if (has_local_palette) {
- bytestream2_get_buffer(&s->gb, s->local_palette, 3 * (1 << bits_per_pixel));
- palette = s->local_palette;
+ pal_size = 1 << bits_per_pixel;
+
+ if (bytestream2_get_bytes_left(&s->gb) < pal_size * 3)
+ return AVERROR_INVALIDDATA;
+
+ gif_read_palette(s, s->local_palette, pal_size);
+ pal = s->local_palette;
} else {
- palette = s->global_palette;
- bits_per_pixel = s->bits_per_pixel;
+ if (!s->has_global_palette) {
+ av_log(s->avctx, AV_LOG_ERROR, "picture doesn't have either global or local palette.\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ pal = s->global_palette;
+ }
+
+ if (s->keyframe) {
+ if (s->transparent_color_index == -1 && s->has_global_palette) {
+ /* transparency wasn't set before the first frame, fill with background color */
+ gif_fill(frame, s->bg_color);
+ } else {
+ /* otherwise fill with transparent color.
+ * this is necessary since by default picture filled with 0x80808080. */
+ gif_fill(frame, s->trans_color);
+ }
}
/* verify that all the image is inside the screen dimensions */
if (left + width > s->screen_width ||
- top + height > s->screen_height ||
- !width || !height) {
+ top + height > s->screen_height) {
+ av_log(s->avctx, AV_LOG_ERROR, "image is outside the screen dimensions.\n");
+ return AVERROR_INVALIDDATA;
+ }
+ if (width <= 0 || height <= 0) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid image dimensions.\n");
return AVERROR_INVALIDDATA;
}
- /* build the palette */
- n = (1 << bits_per_pixel);
- spal = palette;
- for(i = 0; i < n; i++) {
- s->image_palette[i] = (0xffu << 24) | AV_RB24(spal);
- spal += 3;
+ /* process disposal method */
+ if (s->gce_prev_disposal == GCE_DISPOSAL_BACKGROUND) {
+ gif_fill_rect(frame, s->stored_bg_color, s->gce_l, s->gce_t, s->gce_w, s->gce_h);
+ } else if (s->gce_prev_disposal == GCE_DISPOSAL_RESTORE) {
+ gif_copy_img_rect(s->stored_img, (uint32_t *)frame->data[0],
+ frame->linesize[0] / sizeof(uint32_t), s->gce_l, s->gce_t, s->gce_w, s->gce_h);
}
- for(; i < 256; i++)
- s->image_palette[i] = (0xffu << 24);
- /* handle transparency */
- if (s->transparent_color_index >= 0)
- s->image_palette[s->transparent_color_index] = 0;
+
+ s->gce_prev_disposal = s->gce_disposal;
+
+ if (s->gce_disposal != GCE_DISPOSAL_NONE) {
+ s->gce_l = left; s->gce_t = top;
+ s->gce_w = width; s->gce_h = height;
+
+ if (s->gce_disposal == GCE_DISPOSAL_BACKGROUND) {
+ if (s->transparent_color_index >= 0)
+ s->stored_bg_color = s->trans_color;
+ else
+ s->stored_bg_color = s->bg_color;
+ } else if (s->gce_disposal == GCE_DISPOSAL_RESTORE) {
+ av_fast_malloc(&s->stored_img, &s->stored_img_size, frame->linesize[0] * frame->height);
+ if (!s->stored_img)
+ return AVERROR(ENOMEM);
+
+ gif_copy_img_rect((uint32_t *)frame->data[0], s->stored_img,
+ frame->linesize[0] / sizeof(uint32_t), left, top, width, height);
+ }
+ }
+
+ /* Expect at least 2 bytes: 1 for lzw code size and 1 for block size. */
+ if (bytestream2_get_bytes_left(&s->gb) < 2)
+ return AVERROR_INVALIDDATA;
/* now get the image data */
- code_size = bytestream2_get_byte(&s->gb);
- ff_lzw_decode_init(s->lzw, code_size, s->gb.buffer,
- bytestream2_get_bytes_left(&s->gb), FF_LZW_GIF);
+ code_size = bytestream2_get_byteu(&s->gb);
+ if ((ret = ff_lzw_decode_init(s->lzw, code_size, s->gb.buffer,
+ bytestream2_get_bytes_left(&s->gb), FF_LZW_GIF)) < 0) {
+ av_log(s->avctx, AV_LOG_ERROR, "LZW init failed\n");
+ return ret;
+ }
/* read all the image */
- linesize = frame->linesize[0];
- ptr1 = frame->data[0] + top * linesize + left;
+ linesize = frame->linesize[0] / sizeof(uint32_t);
+ ptr1 = (uint32_t *)frame->data[0] + top * linesize + left;
ptr = ptr1;
pass = 0;
y1 = 0;
for (y = 0; y < height; y++) {
- ff_lzw_decode(s->lzw, ptr, width);
+ int count = ff_lzw_decode(s->lzw, s->idx_line, width);
+ if (count != width) {
+ if (count)
+ av_log(s->avctx, AV_LOG_ERROR, "LZW decode failed\n");
+ goto decode_tail;
+ }
+
+ pr = ptr + width;
+
+ for (px = ptr, idx = s->idx_line; px < pr; px++, idx++) {
+ if (*idx != s->transparent_color_index)
+ *px = pal[*idx];
+ }
+
if (is_interleaved) {
switch(pass) {
default:
@@ -149,53 +282,76 @@ static int gif_read_image(GifState *s, AVFrame *frame)
ptr += linesize;
}
}
+
+ decode_tail:
/* read the garbage data until end marker is found */
ff_lzw_decode_tail(s->lzw);
- bytestream2_skip(&s->gb, ff_lzw_size_read(s->lzw));
+ /* Graphic Control Extension's scope is single frame.
+ * Remove its influence. */
+ s->transparent_color_index = -1;
+ s->gce_disposal = GCE_DISPOSAL_NONE;
+
return 0;
}
static int gif_read_extension(GifState *s)
{
- int ext_code, ext_len, i, gce_flags, gce_transparent_index;
+ int ext_code, ext_len, gce_flags, gce_transparent_index;
+
+ /* There must be at least 2 bytes:
+ * 1 for extension label and 1 for extension length. */
+ if (bytestream2_get_bytes_left(&s->gb) < 2)
+ return AVERROR_INVALIDDATA;
- /* extension */
- ext_code = bytestream2_get_byte(&s->gb);
- ext_len = bytestream2_get_byte(&s->gb);
+ ext_code = bytestream2_get_byteu(&s->gb);
+ ext_len = bytestream2_get_byteu(&s->gb);
- av_dlog(s->avctx, "gif: ext_code=0x%x len=%d\n", ext_code, ext_len);
+ av_dlog(s->avctx, "ext_code=0x%x len=%d\n", ext_code, ext_len);
switch(ext_code) {
- case 0xf9:
+ case GIF_GCE_EXT_LABEL:
if (ext_len != 4)
goto discard_ext;
- s->transparent_color_index = -1;
- gce_flags = bytestream2_get_byte(&s->gb);
- s->gce_delay = bytestream2_get_le16(&s->gb);
- gce_transparent_index = bytestream2_get_byte(&s->gb);
+
+ /* We need at least 5 bytes more: 4 is for extension body
+ * and 1 for next block size. */
+ if (bytestream2_get_bytes_left(&s->gb) < 5)
+ return AVERROR_INVALIDDATA;
+
+ gce_flags = bytestream2_get_byteu(&s->gb);
+ bytestream2_skipu(&s->gb, 2); // delay during which the frame is shown
+ gce_transparent_index = bytestream2_get_byteu(&s->gb);
if (gce_flags & 0x01)
s->transparent_color_index = gce_transparent_index;
else
s->transparent_color_index = -1;
s->gce_disposal = (gce_flags >> 2) & 0x7;
- av_dlog(s->avctx, "gif: gce_flags=%x delay=%d tcolor=%d disposal=%d\n",
- gce_flags, s->gce_delay,
+ av_dlog(s->avctx, "gce_flags=%x tcolor=%d disposal=%d\n",
+ gce_flags,
s->transparent_color_index, s->gce_disposal);
- ext_len = bytestream2_get_byte(&s->gb);
+ if (s->gce_disposal > 3) {
+ s->gce_disposal = GCE_DISPOSAL_NONE;
+ av_dlog(s->avctx, "invalid value in gce_disposal (%d). Using default value of 0.\n", ext_len);
+ }
+
+ ext_len = bytestream2_get_byteu(&s->gb);
break;
}
/* NOTE: many extension blocks can come after */
discard_ext:
- while (ext_len != 0) {
- for (i = 0; i < ext_len; i++)
- bytestream2_get_byte(&s->gb);
- ext_len = bytestream2_get_byte(&s->gb);
+ while (ext_len) {
+ /* There must be at least ext_len bytes and 1 for next block size byte. */
+ if (bytestream2_get_bytes_left(&s->gb) < ext_len + 1)
+ return AVERROR_INVALIDDATA;
- av_dlog(s->avctx, "gif: ext_len1=%d\n", ext_len);
+ bytestream2_skipu(&s->gb, ext_len);
+ ext_len = bytestream2_get_byteu(&s->gb);
+
+ av_dlog(s->avctx, "ext_len1=%d\n", ext_len);
}
return 0;
}
@@ -204,44 +360,48 @@ static int gif_read_header1(GifState *s)
{
uint8_t sig[6];
int v, n;
- int has_global_palette;
+ int background_color_index;
if (bytestream2_get_bytes_left(&s->gb) < 13)
return AVERROR_INVALIDDATA;
/* read gif signature */
- bytestream2_get_buffer(&s->gb, sig, 6);
- if (memcmp(sig, gif87a_sig, 6) != 0 &&
- memcmp(sig, gif89a_sig, 6) != 0)
+ bytestream2_get_bufferu(&s->gb, sig, 6);
+ if (memcmp(sig, gif87a_sig, 6) &&
+ memcmp(sig, gif89a_sig, 6))
return AVERROR_INVALIDDATA;
/* read screen header */
s->transparent_color_index = -1;
- s->screen_width = bytestream2_get_le16(&s->gb);
- s->screen_height = bytestream2_get_le16(&s->gb);
- if( (unsigned)s->screen_width > 32767
- || (unsigned)s->screen_height > 32767){
- av_log(NULL, AV_LOG_ERROR, "picture size too large\n");
- return AVERROR_INVALIDDATA;
- }
+ s->screen_width = bytestream2_get_le16u(&s->gb);
+ s->screen_height = bytestream2_get_le16u(&s->gb);
- v = bytestream2_get_byte(&s->gb);
+ v = bytestream2_get_byteu(&s->gb);
s->color_resolution = ((v & 0x70) >> 4) + 1;
- has_global_palette = (v & 0x80);
+ s->has_global_palette = (v & 0x80);
s->bits_per_pixel = (v & 0x07) + 1;
- s->background_color_index = bytestream2_get_byte(&s->gb);
- bytestream2_get_byte(&s->gb); /* ignored */
+ background_color_index = bytestream2_get_byteu(&s->gb);
+ n = bytestream2_get_byteu(&s->gb);
+ if (n) {
+ s->avctx->sample_aspect_ratio.num = n + 15;
+ s->avctx->sample_aspect_ratio.den = 64;
+ }
- av_dlog(s->avctx, "gif: screen_w=%d screen_h=%d bpp=%d global_palette=%d\n",
+ av_dlog(s->avctx, "screen_w=%d screen_h=%d bpp=%d global_palette=%d\n",
s->screen_width, s->screen_height, s->bits_per_pixel,
- has_global_palette);
+ s->has_global_palette);
- if (has_global_palette) {
+ if (s->has_global_palette) {
+ s->background_color_index = background_color_index;
n = 1 << s->bits_per_pixel;
if (bytestream2_get_bytes_left(&s->gb) < n * 3)
return AVERROR_INVALIDDATA;
- bytestream2_get_buffer(&s->gb, s->global_palette, n * 3);
- }
+
+ gif_read_palette(s, s->global_palette, n);
+ s->bg_color = s->global_palette[s->background_color_index];
+ } else
+ s->background_color_index = -1;
+
return 0;
}
@@ -251,23 +411,24 @@ static int gif_parse_next_image(GifState *s, AVFrame *frame)
int code = bytestream2_get_byte(&s->gb);
int ret;
- av_dlog(s->avctx, "gif: code=%02x '%c'\n", code, code);
+ av_log(s->avctx, AV_LOG_DEBUG, "code=%02x '%c'\n", code, code);
switch (code) {
- case ',':
+ case GIF_IMAGE_SEPARATOR:
return gif_read_image(s, frame);
- case '!':
+ case GIF_EXTENSION_INTRODUCER:
if ((ret = gif_read_extension(s)) < 0)
return ret;
break;
- case ';':
+ case GIF_TRAILER:
/* end of image */
+ return AVERROR_EOF;
default:
- /* error or erroneous EOF */
+ /* erroneous block label */
return AVERROR_INVALIDDATA;
}
}
- return AVERROR_INVALIDDATA;
+ return AVERROR_EOF;
}
static av_cold int gif_decode_init(AVCodecContext *avctx)
@@ -276,38 +437,74 @@ static av_cold int gif_decode_init(AVCodecContext *avctx)
s->avctx = avctx;
+ avctx->pix_fmt = AV_PIX_FMT_RGB32;
+ s->frame = av_frame_alloc();
+ if (!s->frame)
+ return AVERROR(ENOMEM);
ff_lzw_decode_open(&s->lzw);
return 0;
}
-static int gif_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
- AVPacket *avpkt)
+static int gif_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
{
- const uint8_t *buf = avpkt->data;
- int buf_size = avpkt->size;
GifState *s = avctx->priv_data;
- AVFrame *picture = data;
int ret;
- bytestream2_init(&s->gb, buf, buf_size);
- if ((ret = gif_read_header1(s)) < 0)
- return ret;
+ bytestream2_init(&s->gb, avpkt->data, avpkt->size);
- avctx->pix_fmt = AV_PIX_FMT_PAL8;
+ s->frame->pts = avpkt->pts;
+ s->frame->pkt_pts = avpkt->pts;
+ s->frame->pkt_dts = avpkt->dts;
+ av_frame_set_pkt_duration(s->frame, avpkt->duration);
- if ((ret = ff_set_dimensions(avctx, s->screen_width, s->screen_height)) < 0)
- return ret;
+ if (avpkt->size >= 6) {
+ s->keyframe = memcmp(avpkt->data, gif87a_sig, 6) == 0 ||
+ memcmp(avpkt->data, gif89a_sig, 6) == 0;
+ } else {
+ s->keyframe = 0;
+ }
- if ((ret = ff_get_buffer(avctx, picture, 0)) < 0) {
- av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
- return ret;
+ if (s->keyframe) {
+ s->keyframe_ok = 0;
+ s->gce_prev_disposal = GCE_DISPOSAL_NONE;
+ if ((ret = gif_read_header1(s)) < 0)
+ return ret;
+
+ if ((ret = ff_set_dimensions(avctx, s->screen_width, s->screen_height)) < 0)
+ return ret;
+
+ av_frame_unref(s->frame);
+ if ((ret = ff_get_buffer(avctx, s->frame, 0)) < 0)
+ return ret;
+
+ av_fast_malloc(&s->idx_line, &s->idx_line_size, s->screen_width);
+ if (!s->idx_line)
+ return AVERROR(ENOMEM);
+
+ s->frame->pict_type = AV_PICTURE_TYPE_I;
+ s->frame->key_frame = 1;
+ s->keyframe_ok = 1;
+ } else {
+ if (!s->keyframe_ok) {
+ av_log(avctx, AV_LOG_ERROR, "cannot decode frame without keyframe\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ if ((ret = ff_reget_buffer(avctx, s->frame)) < 0)
+ return ret;
+
+ s->frame->pict_type = AV_PICTURE_TYPE_P;
+ s->frame->key_frame = 0;
}
- s->image_palette = (uint32_t *)picture->data[1];
- ret = gif_parse_next_image(s, picture);
+
+ ret = gif_parse_next_image(s, s->frame);
if (ret < 0)
return ret;
+ if ((ret = av_frame_ref(data, s->frame)) < 0)
+ return ret;
*got_frame = 1;
+
return bytestream2_tell(&s->gb);
}
@@ -316,9 +513,29 @@ static av_cold int gif_decode_close(AVCodecContext *avctx)
GifState *s = avctx->priv_data;
ff_lzw_decode_close(&s->lzw);
+ av_frame_free(&s->frame);
+ av_freep(&s->idx_line);
+ av_freep(&s->stored_img);
+
return 0;
}
+static const AVOption options[] = {
+ { "trans_color", "color value (ARGB) that is used instead of transparent color",
+ offsetof(GifState, trans_color), AV_OPT_TYPE_INT,
+ {.i64 = GIF_TRANSPARENT_COLOR}, 0, 0xffffffff,
+ AV_OPT_FLAG_DECODING_PARAM|AV_OPT_FLAG_VIDEO_PARAM },
+ { NULL },
+};
+
+static const AVClass decoder_class = {
+ .class_name = "gif decoder",
+ .item_name = av_default_item_name,
+ .option = options,
+ .version = LIBAVUTIL_VERSION_INT,
+ .category = AV_CLASS_CATEGORY_DECODER,
+};
+
AVCodec ff_gif_decoder = {
.name = "gif",
.long_name = NULL_IF_CONFIG_SMALL("GIF (Graphics Interchange Format)"),
@@ -329,4 +546,5 @@ AVCodec ff_gif_decoder = {
.close = gif_decode_close,
.decode = gif_decode_frame,
.capabilities = CODEC_CAP_DR1,
+ .priv_class = &decoder_class,
};