FFmpeg
iss.c
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1 /*
2  * ISS (.iss) file demuxer
3  * Copyright (c) 2008 Jaikrishnan Menon <realityman@gmx.net>
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  * Funcom ISS file demuxer
25  * @author Jaikrishnan Menon
26  * @see http://wiki.multimedia.cx/index.php?title=FunCom_ISS
27  */
28 
30 #include "avformat.h"
31 #include "internal.h"
32 #include "libavutil/avstring.h"
33 
34 #define ISS_SIG "IMA_ADPCM_Sound"
35 #define ISS_SIG_LEN 15
36 #define MAX_TOKEN_SIZE 20
37 
38 typedef struct IssDemuxContext {
42 
43 static void get_token(AVIOContext *s, char *buf, int maxlen)
44 {
45  int i = 0;
46  char c;
47 
48  while ((c = avio_r8(s))) {
49  if(c == ' ')
50  break;
51  if (i < maxlen-1)
52  buf[i++] = c;
53  }
54 
55  if(!c)
56  avio_r8(s);
57 
58  buf[i] = 0; /* Ensure null terminated, but may be truncated */
59 }
60 
61 static int iss_probe(const AVProbeData *p)
62 {
63  if (strncmp(p->buf, ISS_SIG, ISS_SIG_LEN))
64  return 0;
65 
66  return AVPROBE_SCORE_MAX;
67 }
68 
70 {
71  IssDemuxContext *iss = s->priv_data;
72  AVIOContext *pb = s->pb;
73  AVStream *st;
74  char token[MAX_TOKEN_SIZE];
75  int stereo, rate_divisor;
76 
77  get_token(pb, token, sizeof(token)); //"IMA_ADPCM_Sound"
78  get_token(pb, token, sizeof(token)); //packet size
79  if (sscanf(token, "%d", &iss->packet_size) != 1) {
80  av_log(s, AV_LOG_ERROR, "Failed parsing packet size\n");
81  return AVERROR_INVALIDDATA;
82  }
83  get_token(pb, token, sizeof(token)); //File ID
84  get_token(pb, token, sizeof(token)); //out size
85  get_token(pb, token, sizeof(token)); //stereo
86  if (sscanf(token, "%d", &stereo) != 1) {
87  av_log(s, AV_LOG_ERROR, "Failed parsing stereo flag\n");
88  return AVERROR_INVALIDDATA;
89  }
90  get_token(pb, token, sizeof(token)); //Unknown1
91  get_token(pb, token, sizeof(token)); //RateDivisor
92  if (sscanf(token, "%d", &rate_divisor) != 1) {
93  av_log(s, AV_LOG_ERROR, "Failed parsing rate_divisor\n");
94  return AVERROR_INVALIDDATA;
95  }
96  get_token(pb, token, sizeof(token)); //Unknown2
97  get_token(pb, token, sizeof(token)); //Version ID
98  get_token(pb, token, sizeof(token)); //Size
99 
100  if (iss->packet_size <= 0) {
101  av_log(s, AV_LOG_ERROR, "packet_size %d is invalid\n", iss->packet_size);
102  return AVERROR_INVALIDDATA;
103  }
104 
105  iss->sample_start_pos = avio_tell(pb);
106 
107  st = avformat_new_stream(s, NULL);
108  if (!st)
109  return AVERROR(ENOMEM);
112  if (stereo) {
113  st->codecpar->channels = 2;
115  } else {
116  st->codecpar->channels = 1;
118  }
119  st->codecpar->sample_rate = 44100;
120  if(rate_divisor > 0)
121  st->codecpar->sample_rate /= rate_divisor;
125  st->codecpar->block_align = iss->packet_size;
126  avpriv_set_pts_info(st, 32, 1, st->codecpar->sample_rate);
127 
128  return 0;
129 }
130 
132 {
133  IssDemuxContext *iss = s->priv_data;
134  int ret = av_get_packet(s->pb, pkt, iss->packet_size);
135 
136  if(ret != iss->packet_size)
137  return AVERROR(EIO);
138 
139  pkt->stream_index = 0;
140  pkt->pts = avio_tell(s->pb) - iss->sample_start_pos;
141  if(s->streams[0]->codecpar->channels > 0)
142  pkt->pts /= s->streams[0]->codecpar->channels*2;
143  return 0;
144 }
145 
147  .name = "iss",
148  .long_name = NULL_IF_CONFIG_SMALL("Funcom ISS"),
149  .priv_data_size = sizeof(IssDemuxContext),
153 };
iss_read_packet
static int iss_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: iss.c:131
AVERROR
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
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:760
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
AV_CH_LAYOUT_MONO
#define AV_CH_LAYOUT_MONO
Definition: channel_layout.h:90
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
AVCodecParameters::channels
int channels
Audio only.
Definition: codec_par.h:166
ISS_SIG
#define ISS_SIG
Definition: iss.c:34
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:504
AV_CH_LAYOUT_STEREO
#define AV_CH_LAYOUT_STEREO
Definition: channel_layout.h:91
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
AVInputFormat
Definition: avformat.h:638
av_cold
#define av_cold
Definition: attributes.h:90
s
#define s(width, name)
Definition: cbs_vp9.c:257
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:643
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
iss_read_header
static av_cold int iss_read_header(AVFormatContext *s)
Definition: iss.c:69
AV_CODEC_ID_ADPCM_IMA_ISS
@ AV_CODEC_ID_ADPCM_IMA_ISS
Definition: codec_id.h:380
IssDemuxContext::packet_size
int packet_size
Definition: iss.c:39
IssDemuxContext::sample_start_pos
int sample_start_pos
Definition: iss.c:40
AVFormatContext
Format I/O context.
Definition: avformat.h:1188
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1083
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:527
NULL
#define NULL
Definition: coverity.c:32
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:170
AVIOContext
Bytestream IO Context.
Definition: avio.h:161
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:632
get_token
static void get_token(AVIOContext *s, char *buf, int maxlen)
Definition: iss.c:43
IssDemuxContext
Definition: iss.c:38
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:366
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:177
MAX_TOKEN_SIZE
#define MAX_TOKEN_SIZE
Definition: iss.c:36
av_get_packet
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:197
ret
ret
Definition: filter_design.txt:187
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVStream
Stream structure.
Definition: avformat.h:923
avformat.h
ISS_SIG_LEN
#define ISS_SIG_LEN
Definition: iss.c:35
channel_layout.h
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, 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:1186
AVPacket::stream_index
int stream_index
Definition: packet.h:375
ff_iss_demuxer
const AVInputFormat ff_iss_demuxer
Definition: iss.c:146
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:102
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
AVPacket
This structure stores compressed data.
Definition: packet.h:350
AVCodecParameters::channel_layout
uint64_t channel_layout
Audio only.
Definition: codec_par.h:162
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:89
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
iss_probe
static int iss_probe(const AVProbeData *p)
Definition: iss.c:61
avstring.h