diff options
Diffstat (limited to 'libavcodec/mjpeg_parser.c')
-rw-r--r-- | libavcodec/mjpeg_parser.c | 68 |
1 files changed, 49 insertions, 19 deletions
diff --git a/libavcodec/mjpeg_parser.c b/libavcodec/mjpeg_parser.c index ab654614eb..e548b00f40 100644 --- a/libavcodec/mjpeg_parser.c +++ b/libavcodec/mjpeg_parser.c @@ -4,20 +4,20 @@ * Copyright (c) 2003 Alex Beregszaszi * Copyright (c) 2003-2004 Michael Niedermayer * - * 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 */ @@ -28,27 +28,44 @@ #include "parser.h" +typedef struct MJPEGParserContext{ + ParseContext pc; + int size; +}MJPEGParserContext; /** * Find the end of the current frame in the bitstream. * @return the position of the first byte of the next frame, or -1 */ -static int find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size){ +static int find_frame_end(MJPEGParserContext *m, const uint8_t *buf, int buf_size){ + ParseContext *pc= &m->pc; int vop_found, i; - uint16_t state; + uint32_t state; vop_found= pc->frame_start_found; state= pc->state; i=0; if(!vop_found){ - for(i=0; i<buf_size; i++){ + for(i=0; i<buf_size;){ state= (state<<8) | buf[i]; - if(state == 0xFFD8){ - i++; - vop_found=1; - break; + if(state>=0xFFC00000 && state<=0xFFFEFFFF){ + if(state>=0xFFD80000 && state<=0xFFD8FFFF){ + i++; + vop_found=1; + break; + }else if(state<0xFFD00000 || state>0xFFD9FFFF){ + m->size= (state&0xFFFF)-1; + } } + if(m->size>0){ + int size= FFMIN(buf_size-i, m->size); + i+=size; + m->size-=size; + state=0; + continue; + }else + i++; } } @@ -56,13 +73,25 @@ static int find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size){ /* EOF considered as end of frame */ if (buf_size == 0) return 0; - for(; i<buf_size; i++){ + for(; i<buf_size;){ state= (state<<8) | buf[i]; - if(state == 0xFFD8){ - pc->frame_start_found=0; - pc->state=0; - return i-1; + if(state>=0xFFC00000 && state<=0xFFFEFFFF){ + if(state>=0xFFD80000 && state<=0xFFD8FFFF){ + pc->frame_start_found=0; + pc->state=0; + return i-3; + } else if(state<0xFFD00000 || state>0xFFD9FFFF){ + m->size= (state&0xFFFF)-1; + } } + if(m->size>0){ + int size= FFMIN(buf_size-i, m->size); + i+=size; + m->size-=size; + state=0; + continue; + }else + i++; } } pc->frame_start_found= vop_found; @@ -75,13 +104,14 @@ static int jpeg_parse(AVCodecParserContext *s, const uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size) { - ParseContext *pc = s->priv_data; + MJPEGParserContext *m = s->priv_data; + ParseContext *pc = &m->pc; int next; if(s->flags & PARSER_FLAG_COMPLETE_FRAMES){ next= buf_size; }else{ - next= find_frame_end(pc, buf, buf_size); + next= find_frame_end(m, buf, buf_size); if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) { *poutbuf = NULL; @@ -98,7 +128,7 @@ static int jpeg_parse(AVCodecParserContext *s, AVCodecParser ff_mjpeg_parser = { .codec_ids = { AV_CODEC_ID_MJPEG }, - .priv_data_size = sizeof(ParseContext), + .priv_data_size = sizeof(MJPEGParserContext), .parser_parse = jpeg_parse, .parser_close = ff_parse_close, }; |