/* * H.263 decoder * Copyright (c) 2001 Fabrice Bellard * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at> * * 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 */ /** * @file * H.263 decoder. */ #define UNCHECKED_BITSTREAM_READER 1 #include "libavutil/cpu.h" #include "avcodec.h" #include "error_resilience.h" #include "flv.h" #include "h263.h" #include "h263_parser.h" #include "internal.h" #include "mpeg4video.h" #include "mpeg4video_parser.h" #include "mpegvideo.h" #include "msmpeg4.h" #include "vdpau_internal.h" #include "thread.h" av_cold int ff_h263_decode_init(AVCodecContext *avctx) { MpegEncContext *s = avctx->priv_data; int ret; s->avctx = avctx; s->out_format = FMT_H263; s->width = avctx->coded_width; s->height = avctx->coded_height; s->workaround_bugs = avctx->workaround_bugs; // set defaults ff_MPV_decode_defaults(s); s->quant_precision = 5; s->decode_mb = ff_h263_decode_mb; s->low_delay = 1; if (avctx->codec->id == AV_CODEC_ID_MSS2) avctx->pix_fmt = AV_PIX_FMT_YUV420P; else avctx->pix_fmt = ff_get_format(avctx, avctx->codec->pix_fmts); s->unrestricted_mv = 1; /* select sub codec */ switch (avctx->codec->id) { case AV_CODEC_ID_H263: case AV_CODEC_ID_H263P: s->unrestricted_mv = 0; avctx->chroma_sample_location = AVCHROMA_LOC_CENTER; break; case AV_CODEC_ID_MPEG4: break; case AV_CODEC_ID_MSMPEG4V1: s->h263_pred = 1; s->msmpeg4_version = 1; break; case AV_CODEC_ID_MSMPEG4V2: s->h263_pred = 1; s->msmpeg4_version = 2; break; case AV_CODEC_ID_MSMPEG4V3: s->h263_pred = 1; s->msmpeg4_version = 3; break; case AV_CODEC_ID_WMV1: s->h263_pred = 1; s->msmpeg4_version = 4; break; case AV_CODEC_ID_WMV2: s->h263_pred = 1; s->msmpeg4_version = 5; break; case AV_CODEC_ID_VC1: case AV_CODEC_ID_WMV3: case AV_CODEC_ID_VC1IMAGE: case AV_CODEC_ID_WMV3IMAGE: case AV_CODEC_ID_MSS2: s->h263_pred = 1; s->msmpeg4_version = 6; avctx->chroma_sample_location = AVCHROMA_LOC_LEFT; break; case AV_CODEC_ID_H263I: break; case AV_CODEC_ID_FLV1: s->h263_flv = 1; break; default: av_log(avctx, AV_LOG_ERROR, "Unsupported codec %d\n", avctx->codec->id); return AVERROR(ENOSYS); } s->codec_id = avctx->codec->id; if (avctx->stream_codec_tag == AV_RL32("l263") && avctx->extradata_size == 56 && avctx->extradata[0] == 1) s->ehc_mode = 1; /* for h263, we allocate the images after having read the header */ if (avctx->codec->id != AV_CODEC_ID_H263 && avctx->codec->id != AV_CODEC_ID_H263P && avctx->codec->id != AV_CODEC_ID_MPEG4) if ((ret = ff_MPV_common_init(s)) < 0) return ret; ff_h263dsp_init(&s->h263dsp); ff_h263_decode_init_vlc(); return 0; } av_cold int ff_h263_decode_end(AVCodecContext *avctx) { MpegEncContext *s = avctx->priv_data; ff_MPV_common_end(s); return 0; } /** * Return the number of bytes consumed for building the current frame. */ static int get_consumed_bytes(MpegEncContext *s, int buf_size) { int pos = (get_bits_count(&s->gb) + 7) >> 3; if (s->divx_packed || s->avctx->hwaccel) { /* We would have to scan through the whole buf to handle the weird * reordering ... */ return buf_size; } else if (s->flags & CODEC_FLAG_TRUNCATED) { pos -= s->parse_context.last_index; // padding is not really read so this might be -1 if (pos < 0) pos = 0; return pos; } else { // avoid infinite loops (maybe not needed...) if (pos == 0) pos = 1; // oops ;) if (pos + 10 > buf_size) pos = buf_size; return pos; } } static int decode_slice(MpegEncContext *s) { const int part_mask = s->partitioned_frame ? (ER_AC_END | ER_AC_ERROR) : 0x7F; const int mb_size = 16 >> s->avctx->lowres; int ret; s->last_resync_gb = s->gb; s->first_slice_line = 1; s->resync_mb_x = s->mb_x; s->resync_mb_y = s->mb_y; ff_set_qscale(s, s->qscale); if (s->avctx->hwaccel) { const uint8_t *start = s->gb.buffer + get_bits_count(&s->gb) / 8; ret = s->avctx->hwaccel->decode_slice(s->avctx, start, s->gb.buffer_end - start); // ensure we exit decode loop s->mb_y = s->mb_height; return ret; } if (s->partitioned_frame) { const int qscale = s->qscale; if (CONFIG_MPEG4_DECODER && s->codec_id == AV_CODEC_ID_MPEG4) if ((ret = ff_mpeg4_decode_partitions(s->avctx->priv_data)) < 0) return ret; /* restore variables which were modified */ s->first_slice_line = 1; s->mb_x = s->resync_mb_x; s->mb_y = s->resync_mb_y; ff_set_qscale(s, qscale); } for (; s->mb_y < s->mb_height; s->mb_y++) { /* per-row end of slice checks */ if (s->msmpeg4_version) { if (s->resync_mb_y + s->slice_height == s->mb_y) { ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x - 1, s->mb_y, ER_MB_END); return 0; } } if (s->msmpeg4_version == 1) { s->last_dc[0] = s->last_dc[1] = s->last_dc[2] = 128; } ff_init_block_index(s); for (; s->mb_x < s->mb_width; s->mb_x++) { int ret; ff_update_block_index(s); if (s->resync_mb_x == s->mb_x && s->resync_mb_y + 1 == s->mb_y) s->first_slice_line = 0; /* DCT & quantize */ s->mv_dir = MV_DIR_FORWARD; s->mv_type = MV_TYPE_16X16; av_dlog(s, "%d %d %06X\n", ret, get_bits_count(&s->gb), show_bits(&s->gb, 24)); tprintf(NULL, "Decoding MB at %dx%d\n", s->mb_x, s->mb_y); ret = s->decode_mb(s, s->block); if (s->pict_type != AV_PICTURE_TYPE_B) ff_h263_update_motion_val(s); if (ret < 0) { const int xy = s->mb_x + s->mb_y * s->mb_stride; if (ret == SLICE_END) { ff_MPV_decode_mb(s, s->block); if (s->loop_filter) ff_h263_loop_filter(s); ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_MB_END & part_mask); s->padding_bug_score--; if (++s->mb_x >= s->mb_width) { s->mb_x = 0; ff_mpeg_draw_horiz_band(s, s->mb_y * mb_size, mb_size); ff_MPV_report_decode_progress(s); s->mb_y++; } return 0; } else if (ret == SLICE_NOEND) { av_log(s->avctx, AV_LOG_ERROR, "Slice mismatch at MB: %d\n", xy); ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x + 1, s->mb_y, ER_MB_END & part_mask); return AVERROR_INVALIDDATA; } av_log(s->avctx, AV_LOG_ERROR, "Error at MB: %d\n", xy); ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_MB_ERROR & part_mask); if (s->err_recognition & AV_EF_IGNORE_ERR) continue; return AVERROR_INVALIDDATA; } ff_MPV_decode_mb(s, s->block); if (s->loop_filter) ff_h263_loop_filter(s); } ff_mpeg_draw_horiz_band(s, s->mb_y * mb_size, mb_size); ff_MPV_report_decode_progress(s); s->mb_x = 0; } av_assert1(s->mb_x == 0 && s->mb_y == s->mb_height); if (s->codec_id == AV_CODEC_ID_MPEG4 && (s->workaround_bugs & FF_BUG_AUTODETECT) && get_bits_left(&s->gb) >= 48 && show_bits(&s->gb, 24) == 0x4010 && !s->data_partitioning) s->padding_bug_score += 32; /* try to detect the padding bug */ if (s->codec_id == AV_CODEC_ID_MPEG4 && (s->workaround_bugs & FF_BUG_AUTODETECT) && get_bits_left(&s->gb) >= 0 && get_bits_left(&s->gb) < 137 && !s->data_partitioning) { const int bits_count = get_bits_count(&s->gb); const int bits_left = s->gb.size_in_bits - bits_count; if (bits_left == 0) { s->padding_bug_score += 16; } else if (bits_left != 1) { int v = show_bits(&s->gb, 8); v |= 0x7F >> (7 - (bits_count & 7)); if (v == 0x7F && bits_left <= 8) s->padding_bug_score--; else if (v == 0x7F && ((get_bits_count(&s->gb) + 8) & 8) && bits_left <= 16) s->padding_bug_score += 4; else s->padding_bug_score++; } } if (s->codec_id == AV_CODEC_ID_H263 && (s->workaround_bugs & FF_BUG_AUTODETECT) && get_bits_left(&s->gb) >= 8 && get_bits_left(&s->gb) < 300 && s->pict_type == AV_PICTURE_TYPE_I && show_bits(&s->gb, 8) == 0 && !s->data_partitioning) { s->padding_bug_score += 32; } if (s->workaround_bugs & FF_BUG_AUTODETECT) { if (s->padding_bug_score > -2 && !s->data_partitioning) s->workaround_bugs |= FF_BUG_NO_PADDING; else s->workaround_bugs &= ~FF_BUG_NO_PADDING; } // handle formats which don't have unique end markers if (s->msmpeg4_version || (s->workaround_bugs & FF_BUG_NO_PADDING)) { // FIXME perhaps solve this more cleanly int left = get_bits_left(&s->gb); int max_extra = 7; /* no markers in M$ crap */ if (s->msmpeg4_version && s->pict_type == AV_PICTURE_TYPE_I) max_extra += 17; /* buggy padding but the frame should still end approximately at * the bitstream end */ if ((s->workaround_bugs & FF_BUG_NO_PADDING) && (s->err_recognition & (AV_EF_BUFFER|AV_EF_AGGRESSIVE))) max_extra += 48; else if ((s->workaround_bugs & FF_BUG_NO_PADDING)) max_extra += 256 * 256 * 256 * 64; if (left > max_extra) av_log(s->avctx, AV_LOG_ERROR, "discarding %d junk bits at end, next would be %X\n", left, show_bits(&s->gb, 24)); else if (left < 0) av_log(s->avctx, AV_LOG_ERROR, "overreading %d bits\n", -left); else ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x - 1, s->mb_y, ER_MB_END); return 0; } av_log(s->avctx, AV_LOG_ERROR, "slice end not reached but screenspace end (%d left %06X, score= %d)\n", get_bits_left(&s->gb), show_bits(&s->gb, 24), s->padding_bug_score); ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_MB_END & part_mask); return AVERROR_INVALIDDATA; } int ff_h263_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt) { const uint8_t *buf = avpkt->data; int buf_size = avpkt->size; MpegEncContext *s = avctx->priv_data; int ret; int slice_ret = 0; AVFrame *pict = data; s->flags = avctx->flags; s->flags2 = avctx->flags2; /* no supplementary picture */ if (buf_size == 0) { /* special case for last picture */ if (s->low_delay == 0 && s->next_picture_ptr) { if ((ret = av_frame_ref(pict, s->next_picture_ptr->f)) < 0) return ret; s->next_picture_ptr = NULL; *got_frame = 1; } return 0; } if (s->flags & CODEC_FLAG_TRUNCATED) { int next; if (CONFIG_MPEG4_DECODER && s->codec_id == AV_CODEC_ID_MPEG4) { next = ff_mpeg4_find_frame_end(&s->parse_context, buf, buf_size); } else if (CONFIG_H263_DECODER && s->codec_id == AV_CODEC_ID_H263) { next = ff_h263_find_frame_end(&s->parse_context, buf, buf_size); } else if (CONFIG_H263P_DECODER && s->codec_id == AV_CODEC_ID_H263P) { next = ff_h263_find_frame_end(&s->parse_context, buf, buf_size); } else { av_log(s->avctx, AV_LOG_ERROR, "this codec does not support truncated bitstreams\n"); return AVERROR(ENOSYS); } if (ff_combine_frame(&s->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0) return buf_size; } retry: if (s->divx_packed && s->bitstream_buffer_size) { int i; for(i=0; i < buf_size-3; i++) { if (buf[i]==0 && buf[i+1]==0 && buf[i+2]==1) { if (buf[i+3]==0xB0) { av_log(s->avctx, AV_LOG_WARNING, "Discarding excessive bitstream in packed xvid\n"); s->bitstream_buffer_size = 0; } break; } } } if (s->bitstream_buffer_size && (s->divx_packed || buf_size < 20)) // divx 5.01+/xvid frame reorder ret = init_get_bits8(&s->gb, s->bitstream_buffer, s->bitstream_buffer_size); else ret = init_get_bits8(&s->gb, buf, buf_size); s->bitstream_buffer_size = 0; if (ret < 0) return ret; if (!s->context_initialized) // we need the idct permutaton for reading a custom matrix if ((ret = ff_MPV_common_init(s)) < 0) return ret; /* We need to set current_picture_ptr before reading the header, * otherwise we cannot store anyting in there */ if (s->current_picture_ptr == NULL || s->current_picture_ptr->f->data[0]) { int i = ff_find_unused_picture(s, 0); if (i < 0) return i; s->current_picture_ptr = &s->picture[i]; } /* let's go :-) */ if (CONFIG_WMV2_DECODER && s->msmpeg4_version == 5) { ret = ff_wmv2_decode_picture_header(s); } else if (CONFIG_MSMPEG4_DECODER && s->msmpeg4_version) { ret = ff_msmpeg4_decode_picture_header(s); } else if (CONFIG_MPEG4_DECODER && avctx->codec_id == AV_CODEC_ID_MPEG4) { if (s->avctx->extradata_size && s->picture_number == 0) { GetBitContext gb; if (init_get_bits8(&gb, s->avctx->extradata, s->avctx->extradata_size) >= 0 ) ff_mpeg4_decode_picture_header(avctx->priv_data, &gb); } ret = ff_mpeg4_decode_picture_header(avctx->priv_data, &s->gb); } else if (CONFIG_H263I_DECODER && s->codec_id == AV_CODEC_ID_H263I) { ret = ff_intel_h263_decode_picture_header(s); } else if (CONFIG_FLV_DECODER && s->h263_flv) { ret = ff_flv_decode_picture_header(s); } else { ret = ff_h263_decode_picture_header(s); } if (ret < 0 || ret == FRAME_SKIPPED) { if ( s->width != avctx->coded_width || s->height != avctx->coded_height) { av_log(s->avctx, AV_LOG_WARNING, "Reverting picture dimensions change due to header decoding failure\n"); s->width = avctx->coded_width; s->height= avctx->coded_height; } } if (ret == FRAME_SKIPPED) return get_consumed_bytes(s, buf_size); /* skip if the header was thrashed */ if (ret < 0) { av_log(s->avctx, AV_LOG_ERROR, "header damaged\n"); return ret; } avctx->has_b_frames = !s->low_delay; if (CONFIG_MPEG4_DECODER && avctx->codec_id == AV_CODEC_ID_MPEG4) { if (ff_mpeg4_workaround_bugs(avctx) == 1) goto retry; } /* After H263 & mpeg4 header decode we have the height, width, * and other parameters. So then we could init the picture. * FIXME: By the way H263 decoder is evolving it should have * an H263EncContext */ if (s->width != avctx->coded_width || s->height != avctx->coded_height || s->context_reinit) { /* H.263 could change picture size any time */ s->context_reinit = 0; ret = ff_set_dimensions(avctx, s->width, s->height); if (ret < 0) return ret; if ((ret = ff_MPV_common_frame_size_change(s))) return ret; } if (s->codec_id == AV_CODEC_ID_H263 || s->codec_id == AV_CODEC_ID_H263P || s->codec_id == AV_CODEC_ID_H263I) s->gob_index = ff_h263_get_gob_height(s); // for skipping the frame s->current_picture.f->pict_type = s->pict_type; s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I; /* skip B-frames if we don't have reference frames */ if (s->last_picture_ptr == NULL && (s->pict_type == AV_PICTURE_TYPE_B || s->droppable)) return get_consumed_bytes(s, buf_size); if ((avctx->skip_frame >= AVDISCARD_NONREF && s->pict_type == AV_PICTURE_TYPE_B) || (avctx->skip_frame >= AVDISCARD_NONKEY && s->pict_type != AV_PICTURE_TYPE_I) || avctx->skip_frame >= AVDISCARD_ALL) return get_consumed_bytes(s, buf_size); if (s->next_p_frame_damaged) { if (s->pict_type == AV_PICTURE_TYPE_B) return get_consumed_bytes(s, buf_size); else s->next_p_frame_damaged = 0; } if ((!s->no_rounding) || s->pict_type == AV_PICTURE_TYPE_B) { s->me.qpel_put = s->dsp.put_qpel_pixels_tab; s->me.qpel_avg = s->dsp.avg_qpel_pixels_tab; } else { s->me.qpel_put = s->dsp.put_no_rnd_qpel_pixels_tab; s->me.qpel_avg = s->dsp.avg_qpel_pixels_tab; } if ((ret = ff_MPV_frame_start(s, avctx)) < 0) return ret; if (!s->divx_packed && !avctx->hwaccel) ff_thread_finish_setup(avctx); if (CONFIG_MPEG4_VDPAU_DECODER && (s->avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)) { ff_vdpau_mpeg4_decode_picture(avctx->priv_data, s->gb.buffer, s->gb.buffer_end - s->gb.buffer); goto frame_end; } if (avctx->hwaccel) { ret = avctx->hwaccel->start_frame(avctx, s->gb.buffer, s->gb.buffer_end - s->gb.buffer); if (ret < 0 ) return ret; } ff_mpeg_er_frame_start(s); /* the second part of the wmv2 header contains the MB skip bits which * are stored in current_picture->mb_type which is not available before * ff_MPV_frame_start() */ if (CONFIG_WMV2_DECODER && s->msmpeg4_version == 5) { ret = ff_wmv2_decode_secondary_picture_header(s); if (ret < 0) return ret; if (ret == 1) goto frame_end; } /* decode each macroblock */ s->mb_x = 0; s->mb_y = 0; slice_ret = decode_slice(s); while (s->mb_y < s->mb_height) { if (s->msmpeg4_version) { if (s->slice_height == 0 || s->mb_x != 0 || (s->mb_y % s->slice_height) != 0 || get_bits_left(&s->gb) < 0) break; } else { int prev_x = s->mb_x, prev_y = s->mb_y; if (ff_h263_resync(s) < 0) break; if (prev_y * s->mb_width + prev_x < s->mb_y * s->mb_width + s->mb_x) s->er.error_occurred = 1; } if (s->msmpeg4_version < 4 && s->h263_pred) ff_mpeg4_clean_buffers(s); if (decode_slice(s) < 0) slice_ret = AVERROR_INVALIDDATA; } if (s->msmpeg4_version && s->msmpeg4_version < 4 && s->pict_type == AV_PICTURE_TYPE_I) if (!CONFIG_MSMPEG4_DECODER || ff_msmpeg4_decode_ext_header(s, buf_size) < 0) s->er.error_status_table[s->mb_num - 1] = ER_MB_ERROR; av_assert1(s->bitstream_buffer_size == 0); frame_end: ff_er_frame_end(&s->er); if (avctx->hwaccel) { ret = avctx->hwaccel->end_frame(avctx); if (ret < 0) return ret; } ff_MPV_frame_end(s); if (CONFIG_MPEG4_DECODER && avctx->codec_id == AV_CODEC_ID_MPEG4) ff_mpeg4_frame_end(avctx, buf, buf_size); if (!s->divx_packed && avctx->hwaccel) ff_thread_finish_setup(avctx); av_assert1(s->current_picture.f->pict_type == s->current_picture_ptr->f->pict_type); av_assert1(s->current_picture.f->pict_type == s->pict_type); if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) { if ((ret = av_frame_ref(pict, s->current_picture_ptr->f)) < 0) return ret; ff_print_debug_info(s, s->current_picture_ptr, pict); ff_mpv_export_qp_table(s, pict, s->current_picture_ptr, FF_QSCALE_TYPE_MPEG1); } else if (s->last_picture_ptr != NULL) { if ((ret = av_frame_ref(pict, s->last_picture_ptr->f)) < 0) return ret; ff_print_debug_info(s, s->last_picture_ptr, pict); ff_mpv_export_qp_table(s, pict, s->last_picture_ptr, FF_QSCALE_TYPE_MPEG1); } if (s->last_picture_ptr || s->low_delay) { if ( pict->format == AV_PIX_FMT_YUV420P && (s->codec_tag == AV_RL32("GEOV") || s->codec_tag == AV_RL32("GEOX"))) { int x, y, p; av_frame_make_writable(pict); for (p=0; p<3; p++) { int w = FF_CEIL_RSHIFT(pict-> width, !!p); int h = FF_CEIL_RSHIFT(pict->height, !!p); int linesize = pict->linesize[p]; for (y=0; y<(h>>1); y++) for (x=0; x<w; x++) FFSWAP(int, pict->data[p][x + y*linesize], pict->data[p][x + (h-1-y)*linesize]); } } *got_frame = 1; } if (slice_ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE)) return ret; else return get_consumed_bytes(s, buf_size); } const enum AVPixelFormat ff_h263_hwaccel_pixfmt_list_420[] = { #if CONFIG_H263_VAAPI_HWACCEL || CONFIG_MPEG4_VAAPI_HWACCEL AV_PIX_FMT_VAAPI_VLD, #endif #if CONFIG_H263_VDPAU_HWACCEL || CONFIG_MPEG4_VDPAU_HWACCEL AV_PIX_FMT_VDPAU, #endif AV_PIX_FMT_YUV420P, AV_PIX_FMT_NONE }; AVCodec ff_h263_decoder = { .name = "h263", .long_name = NULL_IF_CONFIG_SMALL("H.263 / H.263-1996, H.263+ / H.263-1998 / H.263 version 2"), .type = AVMEDIA_TYPE_VIDEO, .id = AV_CODEC_ID_H263, .priv_data_size = sizeof(MpegEncContext), .init = ff_h263_decode_init, .close = ff_h263_decode_end, .decode = ff_h263_decode_frame, .capabilities = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY, .flush = ff_mpeg_flush, .max_lowres = 3, .pix_fmts = ff_h263_hwaccel_pixfmt_list_420, }; AVCodec ff_h263p_decoder = { .name = "h263p", .long_name = NULL_IF_CONFIG_SMALL("H.263 / H.263-1996, H.263+ / H.263-1998 / H.263 version 2"), .type = AVMEDIA_TYPE_VIDEO, .id = AV_CODEC_ID_H263P, .priv_data_size = sizeof(MpegEncContext), .init = ff_h263_decode_init, .close = ff_h263_decode_end, .decode = ff_h263_decode_frame, .capabilities = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY, .flush = ff_mpeg_flush, .max_lowres = 3, .pix_fmts = ff_h263_hwaccel_pixfmt_list_420, };