FFmpeg  4.3.7
apm.c
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1 /*
2  * Rayman 2 APM Demuxer
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 #include "avformat.h"
23 #include "internal.h"
24 #include "riff.h"
25 #include "libavutil/internal.h"
26 #include "libavutil/intreadwrite.h"
27 
28 #define APM_FILE_HEADER_SIZE 20
29 #define APM_VS12_CHUNK_SIZE 76
30 #define APM_MAX_READ_SIZE 4096
31 
32 #define APM_TAG_VS12 MKTAG('v', 's', '1', '2')
33 #define APM_TAG_DATA MKTAG('D', 'A', 'T', 'A')
34 
35 typedef struct APMState {
43 } APMState;
44 
45 typedef struct APMVS12Chunk {
46  uint32_t magic;
47  uint32_t file_size;
48  uint32_t data_size;
49  uint32_t unk1;
50  uint32_t unk2;
52  uint32_t pad[7];
53 } APMVS12Chunk;
54 
55 static void apm_parse_vs12(APMVS12Chunk *vs12, const uint8_t *buf)
56 {
57  vs12->magic = AV_RL32(buf + 0);
58  vs12->file_size = AV_RL32(buf + 4);
59  vs12->data_size = AV_RL32(buf + 8);
60  vs12->unk1 = AV_RL32(buf + 12);
61  vs12->unk2 = AV_RL32(buf + 16);
62 
63  vs12->state.has_saved = AV_RL32(buf + 20);
64  vs12->state.predictor_r = AV_RL32(buf + 24);
65  vs12->state.step_index_r = AV_RL32(buf + 28);
66  vs12->state.saved_r = AV_RL32(buf + 32);
67  vs12->state.predictor_l = AV_RL32(buf + 36);
68  vs12->state.step_index_l = AV_RL32(buf + 40);
69  vs12->state.saved_l = AV_RL32(buf + 44);
70 
71  for (int i = 0; i < FF_ARRAY_ELEMS(vs12->pad); i++)
72  vs12->pad[i] = AV_RL32(buf + 48 + (i * 4));
73 }
74 
75 static int apm_probe(const AVProbeData *p)
76 {
77  if (p->buf_size < 100)
78  return 0;
79 
80  if (AV_RL32(p->buf + 20) != APM_TAG_VS12)
81  return 0;
82 
83  if (AV_RL32(p->buf + 96) != APM_TAG_DATA)
84  return 0;
85 
86  return AVPROBE_SCORE_MAX - 1;
87 }
88 
90 {
91  int64_t ret;
92  AVStream *st;
93  APMVS12Chunk vs12;
95 
96  if (!(st = avformat_new_stream(s, NULL)))
97  return AVERROR(ENOMEM);
98 
99  /* The header starts with a WAVEFORMATEX */
100  if ((ret = ff_get_wav_header(s, s->pb, st->codecpar, APM_FILE_HEADER_SIZE, 0)) < 0)
101  return ret;
102 
103  if (st->codecpar->bits_per_coded_sample != 4)
104  return AVERROR_INVALIDDATA;
105 
106  if (st->codecpar->codec_tag != 0x2000)
107  return AVERROR_INVALIDDATA;
108 
109  /* ff_get_wav_header() does most of the work, but we need to fix a few things. */
111  st->codecpar->codec_tag = 0;
112 
113  if (st->codecpar->channels == 2)
115  else if (st->codecpar->channels == 1)
117  else
118  return AVERROR_INVALIDDATA;
119 
121  st->codecpar->bits_per_raw_sample = 16;
122  st->codecpar->bit_rate = st->codecpar->channels *
123  st->codecpar->sample_rate *
125 
126  if ((ret = avio_read(s->pb, buf, APM_VS12_CHUNK_SIZE)) < 0)
127  return ret;
128  else if (ret != APM_VS12_CHUNK_SIZE)
129  return AVERROR(EIO);
130 
131  apm_parse_vs12(&vs12, buf);
132 
133  if (vs12.magic != APM_TAG_VS12) {
134  return AVERROR_INVALIDDATA;
135  }
136 
137  if (vs12.state.has_saved) {
138  avpriv_request_sample(s, "Saved Samples");
139  return AVERROR_PATCHWELCOME;
140  }
141 
142  if (avio_rl32(s->pb) != APM_TAG_DATA)
143  return AVERROR_INVALIDDATA;
144 
145  if ((ret = ff_alloc_extradata(st->codecpar, 16)) < 0)
146  return ret;
147 
148  AV_WL32(st->codecpar->extradata + 0, vs12.state.predictor_l);
149  AV_WL32(st->codecpar->extradata + 4, vs12.state.step_index_l);
150  AV_WL32(st->codecpar->extradata + 8, vs12.state.predictor_r);
151  AV_WL32(st->codecpar->extradata + 12, vs12.state.step_index_r);
152 
153  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
154  st->start_time = 0;
155  st->duration = vs12.data_size *
156  (8 / st->codecpar->bits_per_coded_sample) /
157  st->codecpar->channels;
158  return 0;
159 }
160 
162 {
163  int ret;
164  AVCodecParameters *par = s->streams[0]->codecpar;
165 
166  /*
167  * For future reference: if files with the `has_saved` field set ever
168  * surface, `saved_l`, and `saved_r` will each contain 8 "saved" samples
169  * that should be sent to the decoder before the actual data.
170  */
171 
172  if ((ret = av_get_packet(s->pb, pkt, APM_MAX_READ_SIZE)) < 0)
173  return ret;
174 
175  pkt->flags &= ~AV_PKT_FLAG_CORRUPT;
176  pkt->stream_index = 0;
177  pkt->duration = ret * (8 / par->bits_per_coded_sample) / par->channels;
178 
179  return 0;
180 }
181 
183  .name = "apm",
184  .long_name = NULL_IF_CONFIG_SMALL("Ubisoft Rayman 2 APM"),
185  .read_probe = apm_probe,
186  .read_header = apm_read_header,
187  .read_packet = apm_read_packet
188 };
#define NULL
Definition: coverity.c:32
int32_t has_saved
Definition: apm.c:36
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int32_t saved_r
Definition: apm.c:39
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:4948
#define avpriv_request_sample(...)
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
uint32_t unk1
Definition: apm.c:49
static AVPacket pkt
#define AV_CH_LAYOUT_STEREO
Definition: apm.c:35
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
int32_t step_index_l
Definition: apm.c:41
int32_t predictor_l
Definition: apm.c:40
Format I/O context.
Definition: avformat.h:1351
uint32_t pad[7]
Definition: apm.c:52
int32_t predictor_r
Definition: apm.c:37
uint8_t
#define APM_FILE_HEADER_SIZE
Definition: apm.c:28
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:373
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4526
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1419
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:307
uint32_t magic
Definition: apm.c:46
uint64_t channel_layout
Audio only.
Definition: codec_par.h:162
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:625
int ff_get_wav_header(AVFormatContext *s, AVIOContext *pb, AVCodecParameters *par, int size, int big_endian)
Definition: riffdec.c:91
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:89
int32_t saved_l
Definition: apm.c:42
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:747
#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:188
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:361
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:444
#define APM_VS12_CHUNK_SIZE
Definition: apm.c:29
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
common internal API header
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:3328
#define APM_TAG_DATA
Definition: apm.c:33
#define APM_MAX_READ_SIZE
Definition: apm.c:30
internal header for RIFF based (de)muxers do NOT include this in end user applications ...
int32_t
#define s(width, name)
Definition: cbs_vp9.c:257
#define AV_RL32
Definition: intreadwrite.h:146
#define FF_ARRAY_ELEMS(a)
Stream structure.
Definition: avformat.h:876
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
AVIOContext * pb
I/O context.
Definition: avformat.h:1393
APMState state
Definition: apm.c:51
static int apm_probe(const AVProbeData *p)
Definition: apm.c:75
uint32_t file_size
Definition: apm.c:47
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
static int apm_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: apm.c:161
int bits_per_raw_sample
This is the number of valid bits in each output sample.
Definition: codec_par.h:115
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:925
int sample_rate
Audio only.
Definition: codec_par.h:170
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
Main libavformat public API header.
AVInputFormat ff_apm_demuxer
Definition: apm.c:182
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:915
signed 16 bits
Definition: samplefmt.h:61
static void apm_parse_vs12(APMVS12Chunk *vs12, const uint8_t *buf)
Definition: apm.c:55
#define AV_PKT_FLAG_CORRUPT
The packet content is corrupted.
Definition: packet.h:389
static int apm_read_header(AVFormatContext *s)
Definition: apm.c:89
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:102
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:74
int channels
Audio only.
Definition: codec_par.h:166
uint32_t unk2
Definition: apm.c:50
#define APM_TAG_VS12
Definition: apm.c:32
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:650
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1023
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:64
uint32_t data_size
Definition: apm.c:48
int stream_index
Definition: packet.h:357
int32_t step_index_r
Definition: apm.c:38
#define AV_CH_LAYOUT_MONO
This structure stores compressed data.
Definition: packet.h:332
#define AV_WL32(p, v)
Definition: intreadwrite.h:426