FFmpeg
alp.c
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1 /*
2  * LEGO Racers ALP (.tun & .pcm) (de)muxer
3  *
4  * Copyright (C) 2020 Zane van Iperen (zane@zanevaniperen.com)
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include "config_components.h"
24 
26 #include "avformat.h"
27 #include "internal.h"
28 #include "mux.h"
29 #include "rawenc.h"
30 #include "libavutil/intreadwrite.h"
31 #include "libavutil/internal.h"
32 #include "libavutil/opt.h"
33 
34 #define ALP_TAG MKTAG('A', 'L', 'P', ' ')
35 #define ALP_MAX_READ_SIZE 4096
36 
37 typedef struct ALPHeader {
38  uint32_t magic; /*< Magic Number, {'A', 'L', 'P', ' '} */
39  uint32_t header_size; /*< Header size (after this). */
40  char adpcm[6]; /*< "ADPCM" */
41  uint8_t unk1; /*< Unknown */
42  uint8_t num_channels; /*< Channel Count. */
43  uint32_t sample_rate; /*< Sample rate, only if header_size >= 12. */
44 } ALPHeader;
45 
46 typedef enum ALPType {
47  ALP_TYPE_AUTO = 0, /*< Autodetect based on file extension. */
48  ALP_TYPE_TUN = 1, /*< Force a .TUN file. */
49  ALP_TYPE_PCM = 2, /*< Force a .PCM file. */
50 } ALPType;
51 
52 typedef struct ALPMuxContext {
53  const AVClass *class;
56 
57 #if CONFIG_ALP_DEMUXER
58 static int alp_probe(const AVProbeData *p)
59 {
60  uint32_t i;
61 
62  if (AV_RL32(p->buf) != ALP_TAG)
63  return 0;
64 
65  /* Only allowed header sizes are 8 and 12. */
66  i = AV_RL32(p->buf + 4);
67  if (i != 8 && i != 12)
68  return 0;
69 
70  if (strncmp("ADPCM", p->buf + 8, 6) != 0)
71  return 0;
72 
73  return AVPROBE_SCORE_MAX - 1;
74 }
75 
76 static int alp_read_header(AVFormatContext *s)
77 {
78  int ret;
79  AVStream *st;
80  ALPHeader *hdr = s->priv_data;
81  AVCodecParameters *par;
82 
83  if ((hdr->magic = avio_rl32(s->pb)) != ALP_TAG)
84  return AVERROR_INVALIDDATA;
85 
86  hdr->header_size = avio_rl32(s->pb);
87 
88  if (hdr->header_size != 8 && hdr->header_size != 12) {
89  return AVERROR_INVALIDDATA;
90  }
91 
92  if ((ret = avio_read(s->pb, hdr->adpcm, sizeof(hdr->adpcm))) < 0)
93  return ret;
94  else if (ret != sizeof(hdr->adpcm))
95  return AVERROR(EIO);
96 
97  if (strncmp("ADPCM", hdr->adpcm, sizeof(hdr->adpcm)) != 0)
98  return AVERROR_INVALIDDATA;
99 
100  hdr->unk1 = avio_r8(s->pb);
101  hdr->num_channels = avio_r8(s->pb);
102 
103  if (hdr->header_size == 8) {
104  /* .TUN music file */
105  hdr->sample_rate = 22050;
106 
107  } else {
108  /* .PCM sound file */
109  hdr->sample_rate = avio_rl32(s->pb);
110  }
111 
112  if (hdr->sample_rate > 44100) {
113  avpriv_request_sample(s, "Sample Rate > 44100");
114  return AVERROR_PATCHWELCOME;
115  }
116 
117  if (!(st = avformat_new_stream(s, NULL)))
118  return AVERROR(ENOMEM);
119 
120  par = st->codecpar;
123  par->format = AV_SAMPLE_FMT_S16;
124  par->sample_rate = hdr->sample_rate;
125 
126  if (hdr->num_channels > 2 || hdr->num_channels == 0)
127  return AVERROR_INVALIDDATA;
128 
130  par->bits_per_coded_sample = 4;
131  par->block_align = 1;
132  par->bit_rate = par->ch_layout.nb_channels *
133  par->sample_rate *
135 
136  avpriv_set_pts_info(st, 64, 1, par->sample_rate);
137  return 0;
138 }
139 
140 static int alp_read_packet(AVFormatContext *s, AVPacket *pkt)
141 {
142  int ret;
143  AVCodecParameters *par = s->streams[0]->codecpar;
144 
145  if ((ret = av_get_packet(s->pb, pkt, ALP_MAX_READ_SIZE)) < 0)
146  return ret;
147 
149  pkt->stream_index = 0;
150  pkt->duration = ret * 2 / par->ch_layout.nb_channels;
151 
152  return 0;
153 }
154 
155 static int alp_seek(AVFormatContext *s, int stream_index,
156  int64_t pts, int flags)
157 {
158  const ALPHeader *hdr = s->priv_data;
159 
160  if (pts != 0)
161  return AVERROR(EINVAL);
162 
163  return avio_seek(s->pb, hdr->header_size + 8, SEEK_SET);
164 }
165 
167  .name = "alp",
168  .long_name = NULL_IF_CONFIG_SMALL("LEGO Racers ALP"),
169  .priv_data_size = sizeof(ALPHeader),
170  .read_probe = alp_probe,
171  .read_header = alp_read_header,
172  .read_packet = alp_read_packet,
173  .read_seek = alp_seek,
174 };
175 #endif
176 
177 #if CONFIG_ALP_MUXER
178 
179 static int alp_write_init(AVFormatContext *s)
180 {
181  ALPMuxContext *alp = s->priv_data;
182  AVCodecParameters *par;
183 
184  if (alp->type == ALP_TYPE_AUTO) {
185  if (av_match_ext(s->url, "pcm"))
186  alp->type = ALP_TYPE_PCM;
187  else
188  alp->type = ALP_TYPE_TUN;
189  }
190 
191  if (s->nb_streams != 1) {
192  av_log(s, AV_LOG_ERROR, "Too many streams\n");
193  return AVERROR(EINVAL);
194  }
195 
196  par = s->streams[0]->codecpar;
197 
198  if (par->codec_id != AV_CODEC_ID_ADPCM_IMA_ALP) {
199  av_log(s, AV_LOG_ERROR, "%s codec not supported\n",
200  avcodec_get_name(par->codec_id));
201  return AVERROR(EINVAL);
202  }
203 
204  if (par->ch_layout.nb_channels > 2) {
205  av_log(s, AV_LOG_ERROR, "A maximum of 2 channels are supported\n");
206  return AVERROR(EINVAL);
207  }
208 
209  if (par->sample_rate > 44100) {
210  av_log(s, AV_LOG_ERROR, "Sample rate too large\n");
211  return AVERROR(EINVAL);
212  }
213 
214  if (alp->type == ALP_TYPE_TUN && par->sample_rate != 22050) {
215  av_log(s, AV_LOG_ERROR, "Sample rate must be 22050 for TUN files\n");
216  return AVERROR(EINVAL);
217  }
218  return 0;
219 }
220 
221 static int alp_write_header(AVFormatContext *s)
222 {
223  ALPMuxContext *alp = s->priv_data;
224  AVCodecParameters *par = s->streams[0]->codecpar;
225 
226  avio_wl32(s->pb, ALP_TAG);
227  avio_wl32(s->pb, alp->type == ALP_TYPE_PCM ? 12 : 8);
228  avio_write(s->pb, "ADPCM", 6);
229  avio_w8(s->pb, 0);
230  avio_w8(s->pb, par->ch_layout.nb_channels);
231  if (alp->type == ALP_TYPE_PCM)
232  avio_wl32(s->pb, par->sample_rate);
233 
234  return 0;
235 }
236 
238 
239 static const AVOption alp_options[] = {
240  {
241  .name = "type",
242  .help = "set file type",
243  .offset = offsetof(ALPMuxContext, type),
244  .type = AV_OPT_TYPE_INT,
245  .default_val = {.i64 = ALP_TYPE_AUTO},
246  .min = ALP_TYPE_AUTO,
247  .max = ALP_TYPE_PCM,
248  .flags = AE,
249  .unit = "type",
250  },
251  {
252  .name = "auto",
253  .help = "autodetect based on file extension",
254  .offset = 0,
255  .type = AV_OPT_TYPE_CONST,
256  .default_val = {.i64 = ALP_TYPE_AUTO},
257  .min = 0,
258  .max = 0,
259  .flags = AE,
260  .unit = "type"
261  },
262  {
263  .name = "tun",
264  .help = "force .tun, used for music",
265  .offset = 0,
266  .type = AV_OPT_TYPE_CONST,
267  .default_val = {.i64 = ALP_TYPE_TUN},
268  .min = 0,
269  .max = 0,
270  .flags = AE,
271  .unit = "type"
272  },
273  {
274  .name = "pcm",
275  .help = "force .pcm, used for sfx",
276  .offset = 0,
277  .type = AV_OPT_TYPE_CONST,
278  .default_val = {.i64 = ALP_TYPE_PCM},
279  .min = 0,
280  .max = 0,
281  .flags = AE,
282  .unit = "type"
283  },
284  { NULL }
285 };
286 
287 static const AVClass alp_muxer_class = {
288  .class_name = "alp",
289  .item_name = av_default_item_name,
290  .option = alp_options,
291  .version = LIBAVUTIL_VERSION_INT
292 };
293 
295  .p.name = "alp",
296  .p.long_name = NULL_IF_CONFIG_SMALL("LEGO Racers ALP"),
297  .p.extensions = "tun,pcm",
298  .p.audio_codec = AV_CODEC_ID_ADPCM_IMA_ALP,
299  .p.video_codec = AV_CODEC_ID_NONE,
300  .p.priv_class = &alp_muxer_class,
301  .init = alp_write_init,
302  .write_header = alp_write_header,
303  .write_packet = ff_raw_write_packet,
304  .priv_data_size = sizeof(ALPMuxContext)
305 };
306 #endif
AVOutputFormat::name
const char * name
Definition: avformat.h:511
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
opt.h
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
ALPType
ALPType
Definition: alp.c:46
ALPHeader::magic
uint32_t magic
Definition: alp.c:38
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:47
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
AVOption
AVOption.
Definition: opt.h:251
ALPHeader::sample_rate
uint32_t sample_rate
Definition: alp.c:43
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:540
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:323
FFOutputFormat::p
AVOutputFormat p
The public AVOutputFormat.
Definition: mux.h:36
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:464
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: avformat.c:843
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:151
ALPMuxContext
Definition: alp.c:52
ff_alp_demuxer
const AVInputFormat ff_alp_demuxer
type
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf type
Definition: writing_filters.txt:86
pts
static int64_t pts
Definition: transcode_aac.c:643
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:549
AV_PKT_FLAG_CORRUPT
#define AV_PKT_FLAG_CORRUPT
The packet content is corrupted.
Definition: packet.h:578
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_read_callback.c:41
ALP_TYPE_AUTO
@ ALP_TYPE_AUTO
Definition: alp.c:47
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:198
AV_OPT_FLAG_ENCODING_PARAM
#define AV_OPT_FLAG_ENCODING_PARAM
a generic parameter which can be set by the user for muxing or encoding
Definition: opt.h:281
ALPHeader::adpcm
char adpcm[6]
Definition: alp.c:40
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:554
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:454
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
av_match_ext
int av_match_ext(const char *filename, const char *extensions)
Return a positive value if the given filename has one of the given extensions, 0 otherwise.
Definition: format.c:41
ff_raw_write_packet
int ff_raw_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rawenc.c:31
AV_OPT_FLAG_AUDIO_PARAM
#define AV_OPT_FLAG_AUDIO_PARAM
Definition: opt.h:283
AVFormatContext
Format I/O context.
Definition: avformat.h:1363
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:864
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:550
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:237
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:452
FFOutputFormat
Definition: mux.h:32
ff_alp_muxer
const FFOutputFormat ff_alp_muxer
avio_w8
void avio_w8(AVIOContext *s, int b)
Definition: aviobuf.c:226
AE
#define AE
Definition: alacenc.c:636
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:206
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:171
ALPHeader
Definition: alp.c:37
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:777
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:106
AV_CODEC_ID_ADPCM_IMA_ALP
@ AV_CODEC_ID_ADPCM_IMA_ALP
Definition: codec_id.h:416
AVOption::name
const char * name
Definition: opt.h:252
avio_write
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:248
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:650
avio_wl32
void avio_wl32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:404
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:528
ALPHeader::header_size
uint32_t header_size
Definition: alp.c:39
ALP_TYPE_TUN
@ ALP_TYPE_TUN
Definition: alp.c:48
rawenc.h
av_channel_layout_default
void av_channel_layout_default(AVChannelLayout *ch_layout, int nb_channels)
Get the default channel layout for a given number of channels.
Definition: channel_layout.c:1033
avcodec_get_name
const char * avcodec_get_name(enum AVCodecID id)
Get the name of a codec.
Definition: utils.c:417
ALP_TYPE_PCM
@ ALP_TYPE_PCM
Definition: alp.c:49
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:50
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
internal.h
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:178
AV_SAMPLE_FMT_S16
@ AV_SAMPLE_FMT_S16
signed 16 bits
Definition: samplefmt.h:58
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:103
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:841
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:278
AVClass::class_name
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:71
avformat.h
ALP_MAX_READ_SIZE
#define ALP_MAX_READ_SIZE
Definition: alp.c:35
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
channel_layout.h
ALPMuxContext::type
ALPType type
Definition: alp.c:54
ALPHeader::num_channels
uint8_t num_channels
Definition: alp.c:42
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:225
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:659
AVPacket::stream_index
int stream_index
Definition: packet.h:524
ALPHeader::unk1
uint8_t unk1
Definition: alp.c:41
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:29
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:97
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:36
AVCodecParameters::format
int format
Definition: codec_par.h:79
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
AVPacket
This structure stores compressed data.
Definition: packet.h:499
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:84
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
ALP_TAG
#define ALP_TAG
Definition: alp.c:34
AV_OPT_TYPE_CONST
@ AV_OPT_TYPE_CONST
Definition: opt.h:234
mux.h