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 "rawenc.h"
29 #include "libavutil/intreadwrite.h"
30 #include "libavutil/internal.h"
31 #include "libavutil/opt.h"
32 
33 #define ALP_TAG MKTAG('A', 'L', 'P', ' ')
34 #define ALP_MAX_READ_SIZE 4096
35 
36 typedef struct ALPHeader {
37  uint32_t magic; /*< Magic Number, {'A', 'L', 'P', ' '} */
38  uint32_t header_size; /*< Header size (after this). */
39  char adpcm[6]; /*< "ADPCM" */
40  uint8_t unk1; /*< Unknown */
41  uint8_t num_channels; /*< Channel Count. */
42  uint32_t sample_rate; /*< Sample rate, only if header_size >= 12. */
43 } ALPHeader;
44 
45 typedef enum ALPType {
46  ALP_TYPE_AUTO = 0, /*< Autodetect based on file extension. */
47  ALP_TYPE_TUN = 1, /*< Force a .TUN file. */
48  ALP_TYPE_PCM = 2, /*< Force a .PCM file. */
49 } ALPType;
50 
51 typedef struct ALPMuxContext {
52  const AVClass *class;
55 
56 #if CONFIG_ALP_DEMUXER
57 static int alp_probe(const AVProbeData *p)
58 {
59  uint32_t i;
60 
61  if (AV_RL32(p->buf) != ALP_TAG)
62  return 0;
63 
64  /* Only allowed header sizes are 8 and 12. */
65  i = AV_RL32(p->buf + 4);
66  if (i != 8 && i != 12)
67  return 0;
68 
69  if (strncmp("ADPCM", p->buf + 8, 6) != 0)
70  return 0;
71 
72  return AVPROBE_SCORE_MAX - 1;
73 }
74 
75 static int alp_read_header(AVFormatContext *s)
76 {
77  int ret;
78  AVStream *st;
79  ALPHeader *hdr = s->priv_data;
80  AVCodecParameters *par;
81 
82  if ((hdr->magic = avio_rl32(s->pb)) != ALP_TAG)
83  return AVERROR_INVALIDDATA;
84 
85  hdr->header_size = avio_rl32(s->pb);
86 
87  if (hdr->header_size != 8 && hdr->header_size != 12) {
88  return AVERROR_INVALIDDATA;
89  }
90 
91  if ((ret = avio_read(s->pb, hdr->adpcm, sizeof(hdr->adpcm))) < 0)
92  return ret;
93  else if (ret != sizeof(hdr->adpcm))
94  return AVERROR(EIO);
95 
96  if (strncmp("ADPCM", hdr->adpcm, sizeof(hdr->adpcm)) != 0)
97  return AVERROR_INVALIDDATA;
98 
99  hdr->unk1 = avio_r8(s->pb);
100  hdr->num_channels = avio_r8(s->pb);
101 
102  if (hdr->header_size == 8) {
103  /* .TUN music file */
104  hdr->sample_rate = 22050;
105 
106  } else {
107  /* .PCM sound file */
108  hdr->sample_rate = avio_rl32(s->pb);
109  }
110 
111  if (hdr->sample_rate > 44100) {
112  avpriv_request_sample(s, "Sample Rate > 44100");
113  return AVERROR_PATCHWELCOME;
114  }
115 
116  if (!(st = avformat_new_stream(s, NULL)))
117  return AVERROR(ENOMEM);
118 
119  par = st->codecpar;
122  par->format = AV_SAMPLE_FMT_S16;
123  par->sample_rate = hdr->sample_rate;
124 
125  if (hdr->num_channels > 2 || hdr->num_channels == 0)
126  return AVERROR_INVALIDDATA;
127 
129  par->bits_per_coded_sample = 4;
130  par->block_align = 1;
131  par->bit_rate = par->ch_layout.nb_channels *
132  par->sample_rate *
134 
135  avpriv_set_pts_info(st, 64, 1, par->sample_rate);
136  return 0;
137 }
138 
139 static int alp_read_packet(AVFormatContext *s, AVPacket *pkt)
140 {
141  int ret;
142  AVCodecParameters *par = s->streams[0]->codecpar;
143 
144  if ((ret = av_get_packet(s->pb, pkt, ALP_MAX_READ_SIZE)) < 0)
145  return ret;
146 
148  pkt->stream_index = 0;
149  pkt->duration = ret * 2 / par->ch_layout.nb_channels;
150 
151  return 0;
152 }
153 
154 static int alp_seek(AVFormatContext *s, int stream_index,
155  int64_t pts, int flags)
156 {
157  const ALPHeader *hdr = s->priv_data;
158 
159  if (pts != 0)
160  return AVERROR(EINVAL);
161 
162  return avio_seek(s->pb, hdr->header_size + 8, SEEK_SET);
163 }
164 
166  .name = "alp",
167  .long_name = NULL_IF_CONFIG_SMALL("LEGO Racers ALP"),
168  .priv_data_size = sizeof(ALPHeader),
169  .read_probe = alp_probe,
170  .read_header = alp_read_header,
171  .read_packet = alp_read_packet,
172  .read_seek = alp_seek,
173 };
174 #endif
175 
176 #if CONFIG_ALP_MUXER
177 
178 static int alp_write_init(AVFormatContext *s)
179 {
180  ALPMuxContext *alp = s->priv_data;
181  AVCodecParameters *par;
182 
183  if (alp->type == ALP_TYPE_AUTO) {
184  if (av_match_ext(s->url, "pcm"))
185  alp->type = ALP_TYPE_PCM;
186  else
187  alp->type = ALP_TYPE_TUN;
188  }
189 
190  if (s->nb_streams != 1) {
191  av_log(s, AV_LOG_ERROR, "Too many streams\n");
192  return AVERROR(EINVAL);
193  }
194 
195  par = s->streams[0]->codecpar;
196 
197  if (par->codec_id != AV_CODEC_ID_ADPCM_IMA_ALP) {
198  av_log(s, AV_LOG_ERROR, "%s codec not supported\n",
199  avcodec_get_name(par->codec_id));
200  return AVERROR(EINVAL);
201  }
202 
203  if (par->ch_layout.nb_channels > 2) {
204  av_log(s, AV_LOG_ERROR, "A maximum of 2 channels are supported\n");
205  return AVERROR(EINVAL);
206  }
207 
208  if (par->sample_rate > 44100) {
209  av_log(s, AV_LOG_ERROR, "Sample rate too large\n");
210  return AVERROR(EINVAL);
211  }
212 
213  if (alp->type == ALP_TYPE_TUN && par->sample_rate != 22050) {
214  av_log(s, AV_LOG_ERROR, "Sample rate must be 22050 for TUN files\n");
215  return AVERROR(EINVAL);
216  }
217  return 0;
218 }
219 
220 static int alp_write_header(AVFormatContext *s)
221 {
222  ALPMuxContext *alp = s->priv_data;
223  AVCodecParameters *par = s->streams[0]->codecpar;
224 
225  avio_wl32(s->pb, ALP_TAG);
226  avio_wl32(s->pb, alp->type == ALP_TYPE_PCM ? 12 : 8);
227  avio_write(s->pb, "ADPCM", 6);
228  avio_w8(s->pb, 0);
229  avio_w8(s->pb, par->ch_layout.nb_channels);
230  if (alp->type == ALP_TYPE_PCM)
231  avio_wl32(s->pb, par->sample_rate);
232 
233  return 0;
234 }
235 
237 
238 static const AVOption alp_options[] = {
239  {
240  .name = "type",
241  .help = "set file type",
242  .offset = offsetof(ALPMuxContext, type),
243  .type = AV_OPT_TYPE_INT,
244  .default_val = {.i64 = ALP_TYPE_AUTO},
245  .min = ALP_TYPE_AUTO,
246  .max = ALP_TYPE_PCM,
247  .flags = AE,
248  .unit = "type",
249  },
250  {
251  .name = "auto",
252  .help = "autodetect based on file extension",
253  .offset = 0,
254  .type = AV_OPT_TYPE_CONST,
255  .default_val = {.i64 = ALP_TYPE_AUTO},
256  .min = 0,
257  .max = 0,
258  .flags = AE,
259  .unit = "type"
260  },
261  {
262  .name = "tun",
263  .help = "force .tun, used for music",
264  .offset = 0,
265  .type = AV_OPT_TYPE_CONST,
266  .default_val = {.i64 = ALP_TYPE_TUN},
267  .min = 0,
268  .max = 0,
269  .flags = AE,
270  .unit = "type"
271  },
272  {
273  .name = "pcm",
274  .help = "force .pcm, used for sfx",
275  .offset = 0,
276  .type = AV_OPT_TYPE_CONST,
277  .default_val = {.i64 = ALP_TYPE_PCM},
278  .min = 0,
279  .max = 0,
280  .flags = AE,
281  .unit = "type"
282  },
283  { NULL }
284 };
285 
286 static const AVClass alp_muxer_class = {
287  .class_name = "alp",
288  .item_name = av_default_item_name,
289  .option = alp_options,
290  .version = LIBAVUTIL_VERSION_INT
291 };
292 
294  .name = "alp",
295  .long_name = NULL_IF_CONFIG_SMALL("LEGO Racers ALP"),
296  .extensions = "tun,pcm",
297  .audio_codec = AV_CODEC_ID_ADPCM_IMA_ALP,
298  .video_codec = AV_CODEC_ID_NONE,
299  .init = alp_write_init,
300  .write_header = alp_write_header,
301  .write_packet = ff_raw_write_packet,
302  .priv_class = &alp_muxer_class,
303  .priv_data_size = sizeof(ALPMuxContext)
304 };
305 #endif
AVOutputFormat::name
const char * name
Definition: avformat.h:510
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
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: options.c:237
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:57
ALPType
ALPType
Definition: alp.c:45
ALPHeader::magic
uint32_t magic
Definition: alp.c:37
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:53
ff_alp_muxer
const AVOutputFormat ff_alp_muxer
AVOption
AVOption.
Definition: opt.h:251
ALPHeader::sample_rate
uint32_t sample_rate
Definition: alp.c:42
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:392
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:300
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:465
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:697
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:151
ALPMuxContext
Definition: alp.c:51
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:654
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:656
AV_PKT_FLAG_CORRUPT
#define AV_PKT_FLAG_CORRUPT
The packet content is corrupted.
Definition: packet.h:430
ALP_TYPE_AUTO
@ ALP_TYPE_AUTO
Definition: alp.c:46
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:256
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:39
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:661
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:455
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:40
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:1213
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1108
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:529
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
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
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:453
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:960
avio_w8
void avio_w8(AVIOContext *s, int b)
Definition: aviobuf.c:210
AE
#define AE
Definition: alacenc.c:636
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:212
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:177
ALPHeader
Definition: alp.c:36
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:759
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:116
AV_CODEC_ID_ADPCM_IMA_ALP
@ AV_CODEC_ID_ADPCM_IMA_ALP
Definition: codec_id.h:401
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:232
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:632
avio_wl32
void avio_wl32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:386
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:380
ALPHeader::header_size
uint32_t header_size
Definition: alp.c:38
ALP_TYPE_TUN
@ ALP_TYPE_TUN
Definition: alp.c:47
rawenc.h
avcodec_get_name
const char * avcodec_get_name(enum AVCodecID id)
Get the name of a codec.
Definition: utils.c:447
ALP_TYPE_PCM
@ ALP_TYPE_PCM
Definition: alp.c:48
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:48
AVOutputFormat
Definition: avformat.h:509
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
internal.h
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:184
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:102
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:948
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:260
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:34
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:53
ALPHeader::num_channels
uint8_t num_channels
Definition: alp.c:41
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:641
AVPacket::stream_index
int stream_index
Definition: packet.h:376
ALPHeader::unk1
uint8_t unk1
Definition: alp.c:40
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:103
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:36
AVCodecParameters::format
int format
Definition: codec_par.h:85
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:61
AVPacket
This structure stores compressed data.
Definition: packet.h:351
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:90
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:33
AV_OPT_TYPE_CONST
@ AV_OPT_TYPE_CONST
Definition: opt.h:234