yading@11: /*
yading@11:  * RAW Chinese AVS video demuxer
yading@11:  * Copyright (c) 2009  Stefan Gehrer <stefan.gehrer@gmx.de>
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: #include "avformat.h"
yading@11: #include "rawdec.h"
yading@11: 
yading@11: #define CAVS_SEQ_START_CODE       0x000001b0
yading@11: #define CAVS_PIC_I_START_CODE     0x000001b3
yading@11: #define CAVS_UNDEF_START_CODE     0x000001b4
yading@11: #define CAVS_PIC_PB_START_CODE    0x000001b6
yading@11: #define CAVS_VIDEO_EDIT_CODE      0x000001b7
yading@11: #define CAVS_PROFILE_JIZHUN       0x20
yading@11: 
yading@11: static int cavsvideo_probe(AVProbeData *p)
yading@11: {
yading@11:     uint32_t code= -1;
yading@11:     int pic=0, seq=0, slice_pos = 0;
yading@11:     int i;
yading@11: 
yading@11:     for(i=0; i<p->buf_size; i++){
yading@11:         code = (code<<8) + p->buf[i];
yading@11:         if ((code & 0xffffff00) == 0x100) {
yading@11:             if(code < CAVS_SEQ_START_CODE) {
yading@11:                 /* slices have to be consecutive */
yading@11:                 if(code < slice_pos)
yading@11:                     return 0;
yading@11:                 slice_pos = code;
yading@11:             } else {
yading@11:                 slice_pos = 0;
yading@11:             }
yading@11:             if (code == CAVS_SEQ_START_CODE) {
yading@11:                 seq++;
yading@11:                 /* check for the only currently supported profile */
yading@11:                 if(p->buf[i+1] != CAVS_PROFILE_JIZHUN)
yading@11:                     return 0;
yading@11:             } else if ((code == CAVS_PIC_I_START_CODE) ||
yading@11:                        (code == CAVS_PIC_PB_START_CODE)) {
yading@11:                 pic++;
yading@11:             } else if ((code == CAVS_UNDEF_START_CODE) ||
yading@11:                        (code >  CAVS_VIDEO_EDIT_CODE)) {
yading@11:                 return 0;
yading@11:             }
yading@11:         }
yading@11:     }
yading@11:     if(seq && seq*9<=pic*10)
yading@11:         return AVPROBE_SCORE_MAX/2;
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: FF_DEF_RAWVIDEO_DEMUXER(cavsvideo, "raw Chinese AVS (Audio Video Standard)", cavsvideo_probe, NULL, AV_CODEC_ID_CAVS)