yading@11: /*
yading@11:  * Brute Force & Ignorance (BFI) demuxer
yading@11:  * Copyright (c) 2008 Sisir Koppaka
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: /**
yading@11:  * @file
yading@11:  * @brief Brute Force & Ignorance (.bfi) file demuxer
yading@11:  * @author Sisir Koppaka ( sisir.koppaka at gmail dot com )
yading@11:  * @see http://wiki.multimedia.cx/index.php?title=BFI
yading@11:  */
yading@11: 
yading@11: #include "libavutil/channel_layout.h"
yading@11: #include "libavutil/intreadwrite.h"
yading@11: #include "avformat.h"
yading@11: #include "internal.h"
yading@11: 
yading@11: typedef struct BFIContext {
yading@11:     int nframes;
yading@11:     int audio_frame;
yading@11:     int video_frame;
yading@11:     int video_size;
yading@11:     int avflag;
yading@11: } BFIContext;
yading@11: 
yading@11: static int bfi_probe(AVProbeData * p)
yading@11: {
yading@11:     /* Check file header */
yading@11:     if (AV_RL32(p->buf) == MKTAG('B', 'F', '&', 'I'))
yading@11:         return AVPROBE_SCORE_MAX;
yading@11:     else
yading@11:         return 0;
yading@11: }
yading@11: 
yading@11: static int bfi_read_header(AVFormatContext * s)
yading@11: {
yading@11:     BFIContext *bfi = s->priv_data;
yading@11:     AVIOContext *pb = s->pb;
yading@11:     AVStream *vstream;
yading@11:     AVStream *astream;
yading@11:     int fps, chunk_header;
yading@11: 
yading@11:     /* Initialize the video codec... */
yading@11:     vstream = avformat_new_stream(s, NULL);
yading@11:     if (!vstream)
yading@11:         return AVERROR(ENOMEM);
yading@11: 
yading@11:     /* Initialize the audio codec... */
yading@11:     astream = avformat_new_stream(s, NULL);
yading@11:     if (!astream)
yading@11:         return AVERROR(ENOMEM);
yading@11: 
yading@11:     /* Set the total number of frames. */
yading@11:     avio_skip(pb, 8);
yading@11:     chunk_header           = avio_rl32(pb);
yading@11:     bfi->nframes           = avio_rl32(pb);
yading@11:     avio_rl32(pb);
yading@11:     avio_rl32(pb);
yading@11:     avio_rl32(pb);
yading@11:     fps                    = avio_rl32(pb);
yading@11:     avio_skip(pb, 12);
yading@11:     vstream->codec->width  = avio_rl32(pb);
yading@11:     vstream->codec->height = avio_rl32(pb);
yading@11: 
yading@11:     /*Load the palette to extradata */
yading@11:     avio_skip(pb, 8);
yading@11:     vstream->codec->extradata      = av_malloc(768);
yading@11:     vstream->codec->extradata_size = 768;
yading@11:     avio_read(pb, vstream->codec->extradata,
yading@11:                vstream->codec->extradata_size);
yading@11: 
yading@11:     astream->codec->sample_rate = avio_rl32(pb);
yading@11: 
yading@11:     /* Set up the video codec... */
yading@11:     avpriv_set_pts_info(vstream, 32, 1, fps);
yading@11:     vstream->codec->codec_type = AVMEDIA_TYPE_VIDEO;
yading@11:     vstream->codec->codec_id   = AV_CODEC_ID_BFI;
yading@11:     vstream->codec->pix_fmt    = AV_PIX_FMT_PAL8;
yading@11:     vstream->nb_frames         =
yading@11:     vstream->duration          = bfi->nframes;
yading@11: 
yading@11:     /* Set up the audio codec now... */
yading@11:     astream->codec->codec_type      = AVMEDIA_TYPE_AUDIO;
yading@11:     astream->codec->codec_id        = AV_CODEC_ID_PCM_U8;
yading@11:     astream->codec->channels        = 1;
yading@11:     astream->codec->channel_layout  = AV_CH_LAYOUT_MONO;
yading@11:     astream->codec->bits_per_coded_sample = 8;
yading@11:     astream->codec->bit_rate        =
yading@11:         astream->codec->sample_rate * astream->codec->bits_per_coded_sample;
yading@11:     avio_seek(pb, chunk_header - 3, SEEK_SET);
yading@11:     avpriv_set_pts_info(astream, 64, 1, astream->codec->sample_rate);
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: 
yading@11: static int bfi_read_packet(AVFormatContext * s, AVPacket * pkt)
yading@11: {
yading@11:     BFIContext *bfi = s->priv_data;
yading@11:     AVIOContext *pb = s->pb;
yading@11:     int ret, audio_offset, video_offset, chunk_size, audio_size = 0;
yading@11:     if (bfi->nframes == 0 || url_feof(pb)) {
yading@11:         return AVERROR_EOF;
yading@11:     }
yading@11: 
yading@11:     /* If all previous chunks were completely read, then find a new one... */
yading@11:     if (!bfi->avflag) {
yading@11:         uint32_t state = 0;
yading@11:         while(state != MKTAG('S','A','V','I')){
yading@11:             if (url_feof(pb))
yading@11:                 return AVERROR(EIO);
yading@11:             state = 256*state + avio_r8(pb);
yading@11:         }
yading@11:         /* Now that the chunk's location is confirmed, we proceed... */
yading@11:         chunk_size      = avio_rl32(pb);
yading@11:         avio_rl32(pb);
yading@11:         audio_offset    = avio_rl32(pb);
yading@11:         avio_rl32(pb);
yading@11:         video_offset    = avio_rl32(pb);
yading@11:         audio_size      = video_offset - audio_offset;
yading@11:         bfi->video_size = chunk_size - video_offset;
yading@11: 
yading@11:         //Tossing an audio packet at the audio decoder.
yading@11:         ret = av_get_packet(pb, pkt, audio_size);
yading@11:         if (ret < 0)
yading@11:             return ret;
yading@11: 
yading@11:         pkt->pts          = bfi->audio_frame;
yading@11:         bfi->audio_frame += ret;
yading@11:     }
yading@11: 
yading@11:     else {
yading@11: 
yading@11:         //Tossing a video packet at the video decoder.
yading@11:         ret = av_get_packet(pb, pkt, bfi->video_size);
yading@11:         if (ret < 0)
yading@11:             return ret;
yading@11: 
yading@11:         pkt->pts          = bfi->video_frame;
yading@11:         bfi->video_frame += bfi->video_size ? ret / bfi->video_size : 1;
yading@11: 
yading@11:         /* One less frame to read. A cursory decrement. */
yading@11:         bfi->nframes--;
yading@11:     }
yading@11: 
yading@11:     bfi->avflag       = !bfi->avflag;
yading@11:     pkt->stream_index = bfi->avflag;
yading@11:     return ret;
yading@11: }
yading@11: 
yading@11: AVInputFormat ff_bfi_demuxer = {
yading@11:     .name           = "bfi",
yading@11:     .long_name      = NULL_IF_CONFIG_SMALL("Brute Force & Ignorance"),
yading@11:     .priv_data_size = sizeof(BFIContext),
yading@11:     .read_probe     = bfi_probe,
yading@11:     .read_header    = bfi_read_header,
yading@11:     .read_packet    = bfi_read_packet,
yading@11: };