/* * RAW H.264 video demuxer * Copyright (c) 2008 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 "libavcodec/get_bits.h" #include "libavcodec/golomb.h" #include "avformat.h" #include "rawdec.h" #define MAX_SPS_COUNT 32 #define MAX_PPS_COUNT 256 static int h264_probe(const AVProbeData *p) { uint32_t code = -1; int sps = 0, pps = 0, idr = 0, res = 0, sli = 0; int i, ret; int pps_ids[MAX_PPS_COUNT+1] = {0}; int sps_ids[MAX_SPS_COUNT+1] = {0}; unsigned pps_id, sps_id; GetBitContext gb; for (i = 0; i + 2 < p->buf_size; i++) { code = (code << 8) + p->buf[i]; if ((code & 0xffffff00) == 0x100) { int ref_idc = (code >> 5) & 3; int type = code & 0x1F; static const int8_t ref_zero[] = { 2, 0, 0, 0, 0, -1, 1, -1, -1, 1, 1, 1, 1, -1, 2, 2, 2, 2, 2, 0, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2 }; if (code & 0x80) // forbidden_bit return 0; if (ref_zero[type] == 1 && ref_idc) return 0; if (ref_zero[type] == -1 && !ref_idc) return 0; if (ref_zero[type] == 2) { if (!(code == 0x100 && !p->buf[i + 1] && !p->buf[i + 2])) res++; } ret = init_get_bits8(&gb, p->buf + i + 1, p->buf_size - i - 1); if (ret < 0) return 0; switch (type) { case 1: case 5: get_ue_golomb_long(&gb); if (get_ue_golomb_long(&gb) > 9U) return 0; pps_id = get_ue_golomb_long(&gb); if (pps_id > MAX_PPS_COUNT) return 0; if (!pps_ids[pps_id]) break; if (type == 1) sli++; else idr++; break; case 7: skip_bits(&gb, 14); if (get_bits(&gb, 2)) return 0; skip_bits(&gb, 8); sps_id = get_ue_golomb_long(&gb); if (sps_id > MAX_SPS_COUNT) return 0; sps_ids[sps_id] = 1; sps++; break; case 8: pps_id = get_ue_golomb_long(&gb); if (pps_id > MAX_PPS_COUNT) return 0; sps_id = get_ue_golomb_long(&gb); if (sps_id > MAX_SPS_COUNT) return 0; if (!sps_ids[sps_id]) break; pps_ids[pps_id] = 1; pps++; break; } } } ff_tlog(NULL, "sps:%d pps:%d idr:%d sli:%d res:%d\n", sps, pps, idr, sli, res); if (sps && pps && (idr || sli > 3) && res < (sps + pps + idr)) return AVPROBE_SCORE_EXTENSION + 1; // 1 more than .mpg return 0; } FF_DEF_RAWVIDEO_DEMUXER(h264, "raw H.264 video", h264_probe, "h26l,h264,264,avc", AV_CODEC_ID_H264)