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bfi.c
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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 
30 #include "libavutil/intreadwrite.h"
31 #include "avformat.h"
32 #include "internal.h"
33 
34 typedef struct BFIContext {
35  int nframes;
39  int avflag;
40 } BFIContext;
41 
42 static 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 
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->codec->width = avio_rl32(pb);
79  vstream->codec->height = avio_rl32(pb);
80 
81  /*Load the palette to extradata */
82  avio_skip(pb, 8);
83  vstream->codec->extradata = av_malloc(768);
84  if (!vstream->codec->extradata)
85  return AVERROR(ENOMEM);
86  vstream->codec->extradata_size = 768;
87  avio_read(pb, vstream->codec->extradata,
88  vstream->codec->extradata_size);
89 
90  astream->codec->sample_rate = avio_rl32(pb);
91 
92  /* Set up the video codec... */
93  avpriv_set_pts_info(vstream, 32, 1, fps);
95  vstream->codec->codec_id = AV_CODEC_ID_BFI;
96  vstream->codec->pix_fmt = AV_PIX_FMT_PAL8;
97  vstream->nb_frames =
98  vstream->duration = bfi->nframes;
99 
100  /* Set up the audio codec now... */
101  astream->codec->codec_type = AVMEDIA_TYPE_AUDIO;
102  astream->codec->codec_id = AV_CODEC_ID_PCM_U8;
103  astream->codec->channels = 1;
105  astream->codec->bits_per_coded_sample = 8;
106  astream->codec->bit_rate =
107  astream->codec->sample_rate * astream->codec->bits_per_coded_sample;
108  avio_seek(pb, chunk_header - 3, SEEK_SET);
109  avpriv_set_pts_info(astream, 64, 1, astream->codec->sample_rate);
110  return 0;
111 }
112 
113 
115 {
116  BFIContext *bfi = s->priv_data;
117  AVIOContext *pb = s->pb;
118  int ret, audio_offset, video_offset, chunk_size, audio_size = 0;
119  if (bfi->nframes == 0 || avio_feof(pb)) {
120  return AVERROR_EOF;
121  }
122 
123  /* If all previous chunks were completely read, then find a new one... */
124  if (!bfi->avflag) {
125  uint32_t state = 0;
126  while(state != MKTAG('S','A','V','I')){
127  if (avio_feof(pb))
128  return AVERROR(EIO);
129  state = 256*state + avio_r8(pb);
130  }
131  /* Now that the chunk's location is confirmed, we proceed... */
132  chunk_size = avio_rl32(pb);
133  avio_rl32(pb);
134  audio_offset = avio_rl32(pb);
135  avio_rl32(pb);
136  video_offset = avio_rl32(pb);
137  audio_size = video_offset - audio_offset;
138  bfi->video_size = chunk_size - video_offset;
139  if (audio_size < 0 || bfi->video_size < 0) {
140  av_log(s, AV_LOG_ERROR, "Invalid audio/video offsets or chunk size\n");
141  return AVERROR_INVALIDDATA;
142  }
143 
144  //Tossing an audio packet at the audio decoder.
145  ret = av_get_packet(pb, pkt, audio_size);
146  if (ret < 0)
147  return ret;
148 
149  pkt->pts = bfi->audio_frame;
150  bfi->audio_frame += ret;
151  } else if (bfi->video_size > 0) {
152 
153  //Tossing a video packet at the video decoder.
154  ret = av_get_packet(pb, pkt, bfi->video_size);
155  if (ret < 0)
156  return ret;
157 
158  pkt->pts = bfi->video_frame;
159  bfi->video_frame += ret / bfi->video_size;
160 
161  /* One less frame to read. A cursory decrement. */
162  bfi->nframes--;
163  } else {
164  /* Empty video packet */
165  ret = AVERROR(EAGAIN);
166  }
167 
168  bfi->avflag = !bfi->avflag;
169  pkt->stream_index = bfi->avflag;
170  return ret;
171 }
172 
174  .name = "bfi",
175  .long_name = NULL_IF_CONFIG_SMALL("Brute Force & Ignorance"),
176  .priv_data_size = sizeof(BFIContext),
180 };
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:631
Bytestream IO Context.
Definition: avio.h:111
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:4075
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:204
int video_frame
Definition: bfi.c:37
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1721
int audio_frame
Definition: bfi.c:36
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:277
Definition: bfi.c:34
static AVPacket pkt
Format I/O context.
Definition: avformat.h:1273
#define av_malloc(s)
8 bit with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:74
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1616
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3741
#define AVERROR_EOF
End of file.
Definition: error.h:55
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:244
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2995
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:538
int video_size
Definition: bfi.c:38
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
AVInputFormat ff_bfi_demuxer
Definition: bfi.c:173
static int bfi_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: bfi.c:114
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:659
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:175
static int bfi_probe(AVProbeData *p)
Definition: bfi.c:42
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:2322
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:529
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:861
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:450
int bit_rate
the average bitrate
Definition: avcodec.h:1566
audio channel layout utility functions
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
int width
picture width / height.
Definition: avcodec.h:1680
static struct @197 state
static int bfi_read_header(AVFormatContext *s)
Definition: bfi.c:51
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:620
Stream structure.
Definition: avformat.h:842
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
int nframes
Definition: bfi.c:35
enum AVMediaType codec_type
Definition: avcodec.h:1509
enum AVCodecID codec_id
Definition: avcodec.h:1518
int sample_rate
samples per second
Definition: avcodec.h:2261
AVIOContext * pb
I/O context.
Definition: avformat.h:1315
int extradata_size
Definition: avcodec.h:1617
int avflag
Definition: bfi.c:39
This structure contains the data a format has to probe a file.
Definition: avformat.h:448
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:901
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:460
Main libavformat public API header.
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:903
int channels
number of audio channels
Definition: avcodec.h:2262
void * priv_data
Format private data.
Definition: avformat.h:1301
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:628
int avio_feof(AVIOContext *s)
feof() equivalent for AVIOContext.
Definition: aviobuf.c:301
int stream_index
Definition: avcodec.h:1424
#define AV_CH_LAYOUT_MONO
#define MKTAG(a, b, c, d)
Definition: common.h:315
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1399
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1415