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1/*
2 * Brute Force & Ignorance (BFI) demuxer
3 * Copyright (c) 2008 Sisir Koppaka
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22/**
23 * @file
24 * @brief Brute Force & Ignorance (.bfi) file demuxer
25 * @author Sisir Koppaka ( sisir.koppaka at gmail dot com )
26 * @see http://wiki.multimedia.cx/index.php?title=BFI
27 */
28
29#include "libavutil/channel_layout.h"
30#include "libavutil/intreadwrite.h"
31#include "avformat.h"
32#include "internal.h"
33
34typedef struct BFIContext {
35 int nframes;
36 int audio_frame;
37 int video_frame;
38 int video_size;
39 int avflag;
40} BFIContext;
41
42static int bfi_probe(AVProbeData * p)
43{
44 /* Check file header */
45 if (AV_RL32(p->buf) == MKTAG('B', 'F', '&', 'I'))
46 return AVPROBE_SCORE_MAX;
47 else
48 return 0;
49}
50
51static int bfi_read_header(AVFormatContext * s)
52{
53 BFIContext *bfi = s->priv_data;
54 AVIOContext *pb = s->pb;
55 AVStream *vstream;
56 AVStream *astream;
57 int fps, chunk_header;
58
59 /* Initialize the video codec... */
60 vstream = avformat_new_stream(s, NULL);
61 if (!vstream)
62 return AVERROR(ENOMEM);
63
64 /* Initialize the audio codec... */
65 astream = avformat_new_stream(s, NULL);
66 if (!astream)
67 return AVERROR(ENOMEM);
68
69 /* Set the total number of frames. */
70 avio_skip(pb, 8);
71 chunk_header = avio_rl32(pb);
72 bfi->nframes = avio_rl32(pb);
73 avio_rl32(pb);
74 avio_rl32(pb);
75 avio_rl32(pb);
76 fps = avio_rl32(pb);
77 avio_skip(pb, 12);
78 vstream->codecpar->width = avio_rl32(pb);
79 vstream->codecpar->height = avio_rl32(pb);
80
81 /*Load the palette to extradata */
82 avio_skip(pb, 8);
83 vstream->codecpar->extradata = av_malloc(768);
84 if (!vstream->codecpar->extradata)
85 return AVERROR(ENOMEM);
86 vstream->codecpar->extradata_size = 768;
87 avio_read(pb, vstream->codecpar->extradata,
88 vstream->codecpar->extradata_size);
89
90 astream->codecpar->sample_rate = avio_rl32(pb);
91 if (astream->codecpar->sample_rate <= 0) {
92 av_log(s, AV_LOG_ERROR, "Invalid sample rate %d\n", astream->codecpar->sample_rate);
93 return AVERROR_INVALIDDATA;
94 }
95
96 /* Set up the video codec... */
97 avpriv_set_pts_info(vstream, 32, 1, fps);
98 vstream->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
99 vstream->codecpar->codec_id = AV_CODEC_ID_BFI;
100 vstream->codecpar->format = AV_PIX_FMT_PAL8;
101 vstream->nb_frames =
102 vstream->duration = bfi->nframes;
103
104 /* Set up the audio codec now... */
105 astream->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
106 astream->codecpar->codec_id = AV_CODEC_ID_PCM_U8;
107 astream->codecpar->channels = 1;
108 astream->codecpar->channel_layout = AV_CH_LAYOUT_MONO;
109 astream->codecpar->bits_per_coded_sample = 8;
110 astream->codecpar->bit_rate =
111 (int64_t)astream->codecpar->sample_rate * astream->codecpar->bits_per_coded_sample;
112 avio_seek(pb, chunk_header - 3, SEEK_SET);
113 avpriv_set_pts_info(astream, 64, 1, astream->codecpar->sample_rate);
114 return 0;
115}
116
117
118static int bfi_read_packet(AVFormatContext * s, AVPacket * pkt)
119{
120 BFIContext *bfi = s->priv_data;
121 AVIOContext *pb = s->pb;
122 int ret, audio_offset, video_offset, chunk_size, audio_size = 0;
123 if (bfi->nframes == 0 || avio_feof(pb)) {
124 return AVERROR_EOF;
125 }
126
127 /* If all previous chunks were completely read, then find a new one... */
128 if (!bfi->avflag) {
129 uint32_t state = 0;
130 while(state != MKTAG('S','A','V','I')){
131 if (avio_feof(pb))
132 return AVERROR(EIO);
133 state = 256*state + avio_r8(pb);
134 }
135 /* Now that the chunk's location is confirmed, we proceed... */
136 chunk_size = avio_rl32(pb);
137 avio_rl32(pb);
138 audio_offset = avio_rl32(pb);
139 avio_rl32(pb);
140 video_offset = avio_rl32(pb);
141 audio_size = video_offset - audio_offset;
142 bfi->video_size = chunk_size - video_offset;
143 if (audio_size < 0 || bfi->video_size < 0) {
144 av_log(s, AV_LOG_ERROR, "Invalid audio/video offsets or chunk size\n");
145 return AVERROR_INVALIDDATA;
146 }
147
148 //Tossing an audio packet at the audio decoder.
149 ret = av_get_packet(pb, pkt, audio_size);
150 if (ret < 0)
151 return ret;
152
153 pkt->pts = bfi->audio_frame;
154 bfi->audio_frame += ret;
155 } else if (bfi->video_size > 0) {
156
157 //Tossing a video packet at the video decoder.
158 ret = av_get_packet(pb, pkt, bfi->video_size);
159 if (ret < 0)
160 return ret;
161
162 pkt->pts = bfi->video_frame;
163 bfi->video_frame += ret / bfi->video_size;
164
165 /* One less frame to read. A cursory decrement. */
166 bfi->nframes--;
167 } else {
168 /* Empty video packet */
169 ret = AVERROR(EAGAIN);
170 }
171
172 bfi->avflag = !bfi->avflag;
173 pkt->stream_index = bfi->avflag;
174 return ret;
175}
176
177AVInputFormat ff_bfi_demuxer = {
178 .name = "bfi",
179 .long_name = NULL_IF_CONFIG_SMALL("Brute Force & Ignorance"),
180 .priv_data_size = sizeof(BFIContext),
181 .read_probe = bfi_probe,
182 .read_header = bfi_read_header,
183 .read_packet = bfi_read_packet,
184};
185
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