X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fmpeg4video_parser.c;h=246bb9ca4e7e7ff814a12fb55375789d7f720e8a;hb=1f29e5d7a2b0950f3b6820896e97e2c02e6a10a9;hp=4771ca0b443fef1897c63db50e80affc4513b730;hpb=c53d2d90425e0abcca6ff96251bff84fc3993f80;p=ffmpeg diff --git a/libavcodec/mpeg4video_parser.c b/libavcodec/mpeg4video_parser.c index 4771ca0b443..246bb9ca4e7 100644 --- a/libavcodec/mpeg4video_parser.c +++ b/libavcodec/mpeg4video_parser.c @@ -1,100 +1,146 @@ /* * MPEG4 Video frame extraction - * Copyright (c) 2003 Fabrice Bellard. - * Copyright (c) 2003 Michael Niedermayer. + * Copyright (c) 2003 Fabrice Bellard + * Copyright (c) 2003 Michael Niedermayer * - * This file is part of FFmpeg. + * This file is part of Libav. * - * FFmpeg is free software; you can redistribute it and/or + * 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. * - * FFmpeg is distributed in the hope that it will be useful, + * 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 FFmpeg; if not, write to the Free Software + * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ +#include "internal.h" #include "parser.h" #include "mpegvideo.h" +#include "mpeg4video.h" +#include "mpeg4video_parser.h" +struct Mp4vParseContext { + ParseContext pc; + Mpeg4DecContext dec_ctx; + int first_picture; +}; + +int ff_mpeg4_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size) +{ + int vop_found, i; + uint32_t state; + + vop_found = pc->frame_start_found; + state = pc->state; + + i = 0; + if (!vop_found) { + for (i = 0; i < buf_size; i++) { + state = (state << 8) | buf[i]; + if (state == 0x1B6) { + i++; + vop_found = 1; + break; + } + } + } + + if (vop_found) { + /* EOF considered as end of frame */ + if (buf_size == 0) + return 0; + for (; i < buf_size; i++) { + state = (state << 8) | buf[i]; + if ((state & 0xFFFFFF00) == 0x100) { + pc->frame_start_found = 0; + pc->state = -1; + return i - 3; + } + } + } + pc->frame_start_found = vop_found; + pc->state = state; + return END_NOT_FOUND; +} /* XXX: make it use less memory */ -static int av_mpeg4_decode_header(AVCodecParserContext *s1, - AVCodecContext *avctx, - const uint8_t *buf, int buf_size) +static int mpeg4_decode_header(AVCodecParserContext *s1, AVCodecContext *avctx, + const uint8_t *buf, int buf_size) { - ParseContext1 *pc = s1->priv_data; - MpegEncContext *s = pc->enc; + struct Mp4vParseContext *pc = s1->priv_data; + Mpeg4DecContext *dec_ctx = &pc->dec_ctx; + MpegEncContext *s = &dec_ctx->m; GetBitContext gb1, *gb = &gb1; int ret; - s->avctx = avctx; + s->avctx = avctx; s->current_picture_ptr = &s->current_picture; - if (avctx->extradata_size && pc->first_picture){ - init_get_bits(gb, avctx->extradata, avctx->extradata_size*8); - ret = ff_mpeg4_decode_picture_header(s, gb); + if (avctx->extradata_size && pc->first_picture) { + init_get_bits(gb, avctx->extradata, avctx->extradata_size * 8); + ret = ff_mpeg4_decode_picture_header(dec_ctx, gb); } init_get_bits(gb, buf, 8 * buf_size); - ret = ff_mpeg4_decode_picture_header(s, gb); - if (s->width) { - avcodec_set_dimensions(avctx, s->width, s->height); + ret = ff_mpeg4_decode_picture_header(dec_ctx, gb); + if (s->width && (!avctx->width || !avctx->height || + !avctx->coded_width || !avctx->coded_height)) { + ret = ff_set_dimensions(avctx, s->width, s->height); + if (ret < 0) + return ret; } - s1->pict_type= s->pict_type; + s1->pict_type = s->pict_type; pc->first_picture = 0; return ret; } -static int mpeg4video_parse_init(AVCodecParserContext *s) +static av_cold int mpeg4video_parse_init(AVCodecParserContext *s) { - ParseContext1 *pc = s->priv_data; + struct Mp4vParseContext *pc = s->priv_data; - pc->enc = av_mallocz(sizeof(MpegEncContext)); - if (!pc->enc) - return -1; - pc->first_picture = 1; + pc->first_picture = 1; + pc->dec_ctx.m.slice_context_count = 1; return 0; } static int mpeg4video_parse(AVCodecParserContext *s, - AVCodecContext *avctx, - const uint8_t **poutbuf, int *poutbuf_size, - const uint8_t *buf, int buf_size) + AVCodecContext *avctx, + const uint8_t **poutbuf, int *poutbuf_size, + const uint8_t *buf, int buf_size) { ParseContext *pc = s->priv_data; int next; - if(s->flags & PARSER_FLAG_COMPLETE_FRAMES){ - next= buf_size; - }else{ - next= ff_mpeg4_find_frame_end(pc, buf, buf_size); + if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) { + next = buf_size; + } else { + next = ff_mpeg4_find_frame_end(pc, buf, buf_size); if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) { - *poutbuf = NULL; + *poutbuf = NULL; *poutbuf_size = 0; return buf_size; } } - av_mpeg4_decode_header(s, avctx, buf, buf_size); + mpeg4_decode_header(s, avctx, buf, buf_size); - *poutbuf = buf; + *poutbuf = buf; *poutbuf_size = buf_size; return next; } - -AVCodecParser mpeg4video_parser = { - { CODEC_ID_MPEG4 }, - sizeof(ParseContext1), - mpeg4video_parse_init, - mpeg4video_parse, - ff_parse1_close, - ff_mpeg4video_split, +AVCodecParser ff_mpeg4video_parser = { + .codec_ids = { AV_CODEC_ID_MPEG4 }, + .priv_data_size = sizeof(struct Mp4vParseContext), + .parser_init = mpeg4video_parse_init, + .parser_parse = mpeg4video_parse, + .parser_close = ff_parse_close, + .split = ff_mpeg4video_split, };