| /* |
| * Brute Force & Ignorance (BFI) demuxer |
| * Copyright (c) 2008 Sisir Koppaka |
| * |
| * 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 |
| */ |
| |
| /** |
| * @file |
| * @brief Brute Force & Ignorance (.bfi) file demuxer |
| * @author Sisir Koppaka ( sisir.koppaka at gmail dot com ) |
| * @see http://wiki.multimedia.cx/index.php?title=BFI |
| */ |
| |
| #include "libavutil/channel_layout.h" |
| #include "libavutil/intreadwrite.h" |
| #include "avformat.h" |
| #include "internal.h" |
| |
| typedef struct BFIContext { |
| int nframes; |
| int audio_frame; |
| int video_frame; |
| int video_size; |
| int avflag; |
| } BFIContext; |
| |
| static int bfi_probe(const AVProbeData * p) |
| { |
| /* Check file header */ |
| if (AV_RL32(p->buf) == MKTAG('B', 'F', '&', 'I')) |
| return AVPROBE_SCORE_MAX; |
| else |
| return 0; |
| } |
| |
| static int bfi_read_header(AVFormatContext * s) |
| { |
| BFIContext *bfi = s->priv_data; |
| AVIOContext *pb = s->pb; |
| AVStream *vstream; |
| AVStream *astream; |
| int ret, fps, chunk_header; |
| |
| /* Initialize the video codec... */ |
| vstream = avformat_new_stream(s, NULL); |
| if (!vstream) |
| return AVERROR(ENOMEM); |
| |
| /* Initialize the audio codec... */ |
| astream = avformat_new_stream(s, NULL); |
| if (!astream) |
| return AVERROR(ENOMEM); |
| |
| /* Set the total number of frames. */ |
| avio_skip(pb, 8); |
| chunk_header = avio_rl32(pb); |
| bfi->nframes = avio_rl32(pb); |
| avio_rl32(pb); |
| avio_rl32(pb); |
| avio_rl32(pb); |
| fps = avio_rl32(pb); |
| avio_skip(pb, 12); |
| vstream->codecpar->width = avio_rl32(pb); |
| vstream->codecpar->height = avio_rl32(pb); |
| |
| /*Load the palette to extradata */ |
| avio_skip(pb, 8); |
| ret = ff_get_extradata(s, vstream->codecpar, pb, 768); |
| if (ret < 0) |
| return ret; |
| |
| astream->codecpar->sample_rate = avio_rl32(pb); |
| if (astream->codecpar->sample_rate <= 0) { |
| av_log(s, AV_LOG_ERROR, "Invalid sample rate %d\n", astream->codecpar->sample_rate); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| /* Set up the video codec... */ |
| avpriv_set_pts_info(vstream, 32, 1, fps); |
| vstream->codecpar->codec_type = AVMEDIA_TYPE_VIDEO; |
| vstream->codecpar->codec_id = AV_CODEC_ID_BFI; |
| vstream->codecpar->format = AV_PIX_FMT_PAL8; |
| vstream->nb_frames = |
| vstream->duration = bfi->nframes; |
| |
| /* Set up the audio codec now... */ |
| astream->codecpar->codec_type = AVMEDIA_TYPE_AUDIO; |
| astream->codecpar->codec_id = AV_CODEC_ID_PCM_U8; |
| astream->codecpar->channels = 1; |
| astream->codecpar->channel_layout = AV_CH_LAYOUT_MONO; |
| astream->codecpar->bits_per_coded_sample = 8; |
| astream->codecpar->bit_rate = |
| (int64_t)astream->codecpar->sample_rate * astream->codecpar->bits_per_coded_sample; |
| avio_seek(pb, chunk_header - 3, SEEK_SET); |
| avpriv_set_pts_info(astream, 64, 1, astream->codecpar->sample_rate); |
| return 0; |
| } |
| |
| |
| static int bfi_read_packet(AVFormatContext * s, AVPacket * pkt) |
| { |
| BFIContext *bfi = s->priv_data; |
| AVIOContext *pb = s->pb; |
| int ret, audio_offset, video_offset, chunk_size, audio_size = 0; |
| if (bfi->nframes == 0 || avio_feof(pb)) { |
| return AVERROR_EOF; |
| } |
| |
| /* If all previous chunks were completely read, then find a new one... */ |
| if (!bfi->avflag) { |
| uint32_t state = 0; |
| while(state != MKTAG('S','A','V','I')){ |
| if (avio_feof(pb)) |
| return AVERROR(EIO); |
| state = 256*state + avio_r8(pb); |
| } |
| /* Now that the chunk's location is confirmed, we proceed... */ |
| chunk_size = avio_rl32(pb); |
| avio_rl32(pb); |
| audio_offset = avio_rl32(pb); |
| avio_rl32(pb); |
| video_offset = avio_rl32(pb); |
| audio_size = video_offset - audio_offset; |
| bfi->video_size = chunk_size - video_offset; |
| if (audio_size < 0 || bfi->video_size < 0) { |
| av_log(s, AV_LOG_ERROR, "Invalid audio/video offsets or chunk size\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| //Tossing an audio packet at the audio decoder. |
| ret = av_get_packet(pb, pkt, audio_size); |
| if (ret < 0) |
| return ret; |
| |
| pkt->pts = bfi->audio_frame; |
| bfi->audio_frame += ret; |
| } else if (bfi->video_size > 0) { |
| |
| //Tossing a video packet at the video decoder. |
| ret = av_get_packet(pb, pkt, bfi->video_size); |
| if (ret < 0) |
| return ret; |
| |
| pkt->pts = bfi->video_frame; |
| bfi->video_frame += ret / bfi->video_size; |
| |
| /* One less frame to read. A cursory decrement. */ |
| bfi->nframes--; |
| } else { |
| /* Empty video packet */ |
| ret = AVERROR(EAGAIN); |
| } |
| |
| bfi->avflag = !bfi->avflag; |
| pkt->stream_index = bfi->avflag; |
| return ret; |
| } |
| |
| AVInputFormat ff_bfi_demuxer = { |
| .name = "bfi", |
| .long_name = NULL_IF_CONFIG_SMALL("Brute Force & Ignorance"), |
| .priv_data_size = sizeof(BFIContext), |
| .read_probe = bfi_probe, |
| .read_header = bfi_read_header, |
| .read_packet = bfi_read_packet, |
| }; |