FFmpeg
redspark.c
Go to the documentation of this file.
1 /*
2  * RedSpark demuxer
3  * Copyright (c) 2013 James Almer
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 #include "libavcodec/bytestream.h"
23 #include "libavutil/intreadwrite.h"
24 #include "avformat.h"
25 #include "avio.h"
26 #include "internal.h"
27 
28 #define HEADER_SIZE 4096
29 #define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
30 
31 typedef struct RedSparkContext {
34 
35 static int redspark_probe(const AVProbeData *p)
36 {
37  uint32_t key, data;
38  uint8_t header[8];
39 
40  /* Decrypt first 8 bytes of the header */
41  data = AV_RB32(p->buf);
42  key = data ^ 0x52656453;
43  data ^= key;
44  AV_WB32(header, data);
45  key = rol(key, 11);
46 
47  key += rol(key, 3);
48  data = AV_RB32(p->buf + 4) ^ key;
49  AV_WB32(header + 4, data);
50 
51  if (AV_RB64(header) == AV_RB64("RedSpark"))
52  return AVPROBE_SCORE_MAX;
53 
54  return 0;
55 }
56 
58 {
59  AVIOContext *pb = s->pb;
60  RedSparkContext *redspark = s->priv_data;
61  AVCodecParameters *par;
62  GetByteContext gbc;
63  int i, coef_off, ret = 0;
64  uint32_t key, data;
66  AVStream *st;
67 
68  st = avformat_new_stream(s, NULL);
69  if (!st)
70  return AVERROR(ENOMEM);
71  par = st->codecpar;
72 
73  /* Decrypt header */
74  data = avio_rb32(pb);
75  key = data ^ 0x52656453;
76  data ^= key;
77  AV_WB32(header, data);
78  key = rol(key, 11);
79 
80  for (i = 4; i < HEADER_SIZE; i += 4) {
81  key += rol(key, 3);
82  data = avio_rb32(pb) ^ key;
83  AV_WB32(header + i, data);
84  }
85 
88 
89  bytestream2_init(&gbc, header, HEADER_SIZE);
90  bytestream2_seek(&gbc, 0x3c, SEEK_SET);
91  par->sample_rate = bytestream2_get_be32u(&gbc);
92  if (par->sample_rate <= 0 || par->sample_rate > 96000) {
93  av_log(s, AV_LOG_ERROR, "Invalid sample rate: %d\n", par->sample_rate);
94  return AVERROR_INVALIDDATA;
95  }
96 
97  st->duration = bytestream2_get_be32u(&gbc) * 14;
98  redspark->samples_count = 0;
99  bytestream2_skipu(&gbc, 10);
100  par->channels = bytestream2_get_byteu(&gbc);
101  if (!par->channels) {
102  return AVERROR_INVALIDDATA;
103  }
104 
105  coef_off = 0x54 + par->channels * 8;
106  if (bytestream2_get_byteu(&gbc)) // Loop flag
107  coef_off += 16;
108 
109  if (coef_off + par->channels * (32 + 14) > HEADER_SIZE) {
110  return AVERROR_INVALIDDATA;
111  }
112 
113  if (ff_alloc_extradata(par, 32 * par->channels)) {
114  return AVERROR_INVALIDDATA;
115  }
116 
117  /* Get the ADPCM table */
118  bytestream2_seek(&gbc, coef_off, SEEK_SET);
119  for (i = 0; i < par->channels; i++) {
120  if (bytestream2_get_bufferu(&gbc, par->extradata + i * 32, 32) != 32) {
121  return AVERROR_INVALIDDATA;
122  }
123  bytestream2_skipu(&gbc, 14);
124  }
125 
126  avpriv_set_pts_info(st, 64, 1, par->sample_rate);
127 
128  return ret;
129 }
130 
132 {
133  AVCodecParameters *par = s->streams[0]->codecpar;
134  RedSparkContext *redspark = s->priv_data;
135  uint32_t size = 8 * par->channels;
136  int ret;
137 
138  if (avio_feof(s->pb) || redspark->samples_count == s->streams[0]->duration)
139  return AVERROR_EOF;
140 
141  ret = av_get_packet(s->pb, pkt, size);
142  if (ret != size) {
143  av_packet_unref(pkt);
144  return AVERROR(EIO);
145  }
146 
147  pkt->duration = 14;
148  redspark->samples_count += pkt->duration;
149  pkt->stream_index = 0;
150 
151  return ret;
152 }
153 
155  .name = "redspark",
156  .long_name = NULL_IF_CONFIG_SMALL("RedSpark"),
157  .priv_data_size = sizeof(RedSparkContext),
161  .extensions = "rsd",
162 };
#define rol(value, bits)
Definition: redspark.c:29
#define NULL
Definition: coverity.c:32
Bytestream IO Context.
Definition: avio.h:161
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
Buffered I/O operations.
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
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:4929
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3968
static int redspark_probe(const AVProbeData *p)
Definition: redspark.c:35
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:133
const char * key
static AVPacket pkt
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3960
static av_always_inline unsigned int bytestream2_get_bufferu(GetByteContext *g, uint8_t *dst, unsigned int size)
Definition: bytestream.h:273
Format I/O context.
Definition: avformat.h:1358
uint8_t
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:803
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1498
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4502
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
Definition: bytestream.h:87
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1426
static int redspark_read_header(AVFormatContext *s)
Definition: redspark.c:57
static av_always_inline void bytestream2_skipu(GetByteContext *g, unsigned int size)
Definition: bytestream.h:170
#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:310
ptrdiff_t size
Definition: opengl_enc.c:100
static const uint8_t header[24]
Definition: sdr2.c:67
#define av_log(a,...)
int samples_count
Definition: redspark.c:32
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3964
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
int ff_alloc_extradata(AVCodecParameters *par, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0...
Definition: utils.c:3321
#define s(width, name)
Definition: cbs_vp9.c:257
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:530
Stream structure.
Definition: avformat.h:881
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:599
#define AV_WB32(p, v)
Definition: intreadwrite.h:419
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
AVInputFormat ff_redspark_demuxer
Definition: redspark.c:154
static int redspark_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: redspark.c:131
#define HEADER_SIZE
Definition: redspark.c:28
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:930
int sample_rate
Audio only.
Definition: avcodec.h:4078
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_RB64
Definition: bytestream.h:87
Main libavformat public API header.
void * priv_data
Format private data.
Definition: avformat.h:1386
static av_always_inline int bytestream2_seek(GetByteContext *g, int offset, int whence)
Definition: bytestream.h:208
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: avcodec.h:3982
int channels
Audio only.
Definition: avcodec.h:4074
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:654
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:361
int stream_index
Definition: avcodec.h:1482
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
This structure stores compressed data.
Definition: avcodec.h:1457