/* * RAW MPEG video demuxer * Copyright (c) 2002-2003 Fabrice Bellard * Copyright (c) 2006 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 */ #include "avformat.h" #include "rawdec.h" #include "libavutil/intreadwrite.h" #include "libavcodec/internal.h" #define SEQ_START_CODE 0x000001b3 #define GOP_START_CODE 0x000001b8 #define PICTURE_START_CODE 0x00000100 #define SLICE_START_CODE 0x00000101 #define PACK_START_CODE 0x000001ba #define VIDEO_ID 0x000001e0 #define AUDIO_ID 0x000001c0 static int mpegvideo_probe(AVProbeData *p) { uint32_t code= -1; int pic=0, seq=0, slice=0, pspack=0, vpes=0, apes=0, res=0, sicle=0; const uint8_t *ptr = p->buf, *end = ptr + p->buf_size; uint32_t last = 0; int j; while (ptr < end) { ptr = avpriv_find_start_code(ptr, end, &code); if ((code & 0xffffff00) == 0x100) { switch(code){ case SEQ_START_CODE: if (!(ptr[3 + 1 + 2] & 0x20)) break; j = -1; if (ptr[j + 8] & 2) j+= 64; if (j >= end - ptr) break; if (ptr[j + 8] & 1) j+= 64; if (j >= end - ptr) break; if (AV_RB24(ptr + j + 9) & 0xFFFFFE) break; seq++; break; case PICTURE_START_CODE: pic++; break; case PACK_START_CODE: pspack++; break; case 0x1b6: res++; break; } if (code >= SLICE_START_CODE && code <= 0x1af) { if (last >= SLICE_START_CODE && last <= 0x1af) { if (code >= last) slice++; else sicle++; }else{ if (code == SLICE_START_CODE) slice++; else sicle++; } } if ((code & 0x1f0) == VIDEO_ID) vpes++; else if((code & 0x1e0) == AUDIO_ID) apes++; last = code; } } if(seq && seq*9<=pic*10 && pic*9<=slice*10 && !pspack && !apes && !res && slice > sicle) { if(vpes) return AVPROBE_SCORE_EXTENSION / 4; else return pic>1 ? AVPROBE_SCORE_EXTENSION + 1 : AVPROBE_SCORE_EXTENSION / 2; // +1 for .mpg } return 0; } FF_DEF_RAWVIDEO_DEMUXER(mpegvideo, "raw MPEG video", mpegvideo_probe, NULL, AV_CODEC_ID_MPEG1VIDEO)