| /* |
| * 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" |
| #include "libavcodec/internal.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) |