|
- /*
- * RAW MPEG-4 video demuxer
- * Copyright (c) 2006 Thijs Vermeir <thijs.vermeir@barco.com>
- *
- * This file is part of Libav.
- *
- * Libav 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,
- * 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
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
- #include "avformat.h"
- #include "rawdec.h"
-
- #define VISUAL_OBJECT_START_CODE 0x000001b5
- #define VOP_START_CODE 0x000001b6
-
- static int mpeg4video_probe(AVProbeData *probe_packet)
- {
- uint32_t temp_buffer = -1;
- int VO = 0, VOL = 0, VOP = 0, VISO = 0, res = 0;
- int i;
-
- for (i = 0; i < probe_packet->buf_size; i++) {
- temp_buffer = (temp_buffer << 8) + probe_packet->buf[i];
- if (temp_buffer & 0xfffffe00)
- continue;
- if (temp_buffer < 2)
- continue;
-
- if (temp_buffer == VOP_START_CODE)
- VOP++;
- else if (temp_buffer == VISUAL_OBJECT_START_CODE)
- VISO++;
- else if (temp_buffer >= 0x100 && temp_buffer < 0x120)
- VO++;
- else if (temp_buffer >= 0x120 && temp_buffer < 0x130)
- VOL++;
- else if (!(0x1AF < temp_buffer && temp_buffer < 0x1B7) &&
- !(0x1B9 < temp_buffer && temp_buffer < 0x1C4))
- res++;
- }
-
- if (VOP >= VISO && VOP >= VOL && VO >= VOL && VOL > 0 && res == 0)
- return AVPROBE_SCORE_EXTENSION;
- return 0;
- }
-
- FF_DEF_RAWVIDEO_DEMUXER(m4v, "raw MPEG-4 video", mpeg4video_probe, "m4v",
- AV_CODEC_ID_MPEG4)
|
