From 99392a6111eac44875dfc47eab2a0ea1eb4d24ae Mon Sep 17 00:00:00 2001 From: Aurelien Jacobs Date: Sun, 29 Aug 2010 21:37:37 +0000 Subject: move h261 demuxer to its own file Originally committed as revision 24980 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavformat/h261dec.c | 75 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 75 insertions(+) create mode 100644 libavformat/h261dec.c (limited to 'libavformat/h261dec.c') diff --git a/libavformat/h261dec.c b/libavformat/h261dec.c new file mode 100644 index 0000000000..936415c7e0 --- /dev/null +++ b/libavformat/h261dec.c @@ -0,0 +1,75 @@ +/* + * RAW H.261 video demuxer + * Copyright (c) 2009 Michael Niedermayer + * + * 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 "avformat.h" +#include "raw.h" + +static int h261_probe(AVProbeData *p) +{ + uint32_t code= -1; + int i; + int valid_psc=0; + int invalid_psc=0; + int next_gn=0; + int src_fmt=0; + GetBitContext gb; + + init_get_bits(&gb, p->buf, p->buf_size*8); + + for(i=0; ibuf_size*8; i++){ + if ((code & 0x01ff0000) || !(code & 0xff00)) { + code = (code<<8) + get_bits(&gb, 8); + i += 7; + } else + code = (code<<1) + get_bits1(&gb); + if ((code & 0xffff0000) == 0x10000) { + int gn= (code>>12)&0xf; + if(!gn) + src_fmt= code&8; + if(gn != next_gn) invalid_psc++; + else valid_psc++; + + if(src_fmt){ // CIF + next_gn= (gn+1 )%13; + }else{ //QCIF + next_gn= (gn+1+!!gn)% 7; + } + } + } + if(valid_psc > 2*invalid_psc + 6){ + return 50; + }else if(valid_psc > 2*invalid_psc + 2) + return 25; + return 0; +} + +AVInputFormat h261_demuxer = { + "h261", + NULL_IF_CONFIG_SMALL("raw H.261"), + 0, + h261_probe, + ff_raw_video_read_header, + ff_raw_read_partial_packet, + .flags= AVFMT_GENERIC_INDEX, + .extensions = "h261", + .value = CODEC_ID_H261, +}; -- cgit v1.2.3