FFmpeg: libavformat/libgme.c Source File

FFmpeg
libgme.c
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 /**
20 * @file
21 * libgme demuxer
22 */
23 
24 #include <gme/gme.h>
25 #include "libavutil/avstring.h"
26 #include "libavutil/eval.h"
27 #include "libavutil/opt.h"
28 #include "avformat.h"
29 #include "internal.h"
30 
31  typedef struct GMEContext {
32   const AVClass *class;
33   Music_Emu *music_emu;
34   gme_info_t *info; ///< selected track
35 
36  /* options */
37   int track_index;
38   int sample_rate;
39   int64_t max_size;
40 } GMEContext;
41 
42  #define OFFSET(x) offsetof(GMEContext, x)
43  #define A AV_OPT_FLAG_AUDIO_PARAM
44  #define D AV_OPT_FLAG_DECODING_PARAM
45  static const AVOption options[] = {
46  {"track_index", "set track that should be played", OFFSET(track_index), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, A|D},
47  {"sample_rate", "set sample rate", OFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64 = 44100}, 1000, 999999, A|D},
48  {"max_size", "set max file size supported (in bytes)", OFFSET(max_size), AV_OPT_TYPE_INT64, {.i64 = 50 * 1024 * 1024}, 0, SIZE_MAX, A|D},
49  {NULL}
50 };
51 
52  static void add_meta(AVFormatContext *s, const char *name, const char *value)
53 {
54  if (value && value[0])
55  av_dict_set(&s->metadata, name, value, 0);
56 }
57 
58  static int load_metadata(AVFormatContext *s)
59 {
60  GMEContext *gme = s->priv_data;
61  gme_info_t *info = gme->info;
62  char buf[30];
63 
64  add_meta(s, "system", info->system);
65  add_meta(s, "game", info->game);
66  add_meta(s, "song", info->song);
67  add_meta(s, "author", info->author);
68  add_meta(s, "copyright", info->copyright);
69  add_meta(s, "comment", info->comment);
70  add_meta(s, "dumper", info->dumper);
71 
72  snprintf(buf, sizeof(buf), "%d", (int)gme_track_count(gme->music_emu));
73  add_meta(s, "tracks", buf);
74 
75  return 0;
76 }
77 
78  #define AUDIO_PKT_SIZE 512
79 
80  static int read_header_gme(AVFormatContext *s)
81 {
82  AVStream *st;
83  AVIOContext *pb = s->pb;
84  GMEContext *gme = s->priv_data;
85  int64_t sz = avio_size(pb);
86  char *buf;
87  char dummy;
88 
89  if (sz < 0) {
90  av_log(s, AV_LOG_WARNING, "Could not determine file size\n");
91  sz = gme->max_size;
92  } else if (gme->max_size && sz > gme->max_size) {
93  sz = gme->max_size;
94  }
95 
96  buf = av_malloc(sz);
97  if (!buf)
98  return AVERROR(ENOMEM);
99  sz = avio_read(pb, buf, sz);
100 
101  // Data left means our buffer (the max_size option) is too small
102  if (avio_read(pb, &dummy, 1) == 1) {
103  av_log(s, AV_LOG_ERROR, "File size is larger than max_size option "
104  "value %"PRIi64", consider increasing the max_size option\n",
105  gme->max_size);
106  return AVERROR_BUFFER_TOO_SMALL;
107  }
108 
109  if (gme_open_data(buf, sz, &gme->music_emu, gme->sample_rate)) {
110  av_freep(&buf);
111  return AVERROR_INVALIDDATA;
112  }
113  av_freep(&buf);
114 
115  if (gme_track_info(gme->music_emu, &gme->info, gme->track_index))
116  return AVERROR_STREAM_NOT_FOUND;
117 
118  if (gme_start_track(gme->music_emu, gme->track_index))
119  return AVERROR_UNKNOWN;
120 
121  load_metadata(s);
122 
123  st = avformat_new_stream(s, NULL);
124  if (!st)
125  return AVERROR(ENOMEM);
126  avpriv_set_pts_info(st, 64, 1, 1000);
127  if (st->duration > 0)
128  st->duration = gme->info->length;
129  st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
130  st->codecpar->codec_id = AV_NE(AV_CODEC_ID_PCM_S16BE, AV_CODEC_ID_PCM_S16LE);
131  st->codecpar->channels = 2;
132  st->codecpar->sample_rate = gme->sample_rate;
133 
134  return 0;
135 }
136 
137  static int read_packet_gme(AVFormatContext *s, AVPacket *pkt)
138 {
139  GMEContext *gme = s->priv_data;
140  int n_samples = AUDIO_PKT_SIZE / 2;
141  int ret;
142 
143  if (gme_track_ended(gme->music_emu))
144  return AVERROR_EOF;
145 
146  if ((ret = av_new_packet(pkt, AUDIO_PKT_SIZE)) < 0)
147  return ret;
148 
149  if (gme_play(gme->music_emu, n_samples, (short *)pkt->data))
150  return AVERROR_EXTERNAL;
151  pkt->size = AUDIO_PKT_SIZE;
152 
153  return 0;
154 }
155 
156  static int read_close_gme(AVFormatContext *s)
157 {
158  GMEContext *gme = s->priv_data;
159  gme_free_info(gme->info);
160  gme_delete(gme->music_emu);
161  return 0;
162 }
163 
164  static int read_seek_gme(AVFormatContext *s, int stream_idx, int64_t ts, int flags)
165 {
166  GMEContext *gme = s->priv_data;
167  if (!gme_seek(gme->music_emu, (int)ts))
168  return AVERROR_EXTERNAL;
169  return 0;
170 }
171 
172  static int probe_gme(AVProbeData *p)
173 {
174  // Reads 4 bytes - returns "" if unknown format.
175  if (gme_identify_header(p->buf)[0]) {
176  if (p->buf_size < 16384)
177  return AVPROBE_SCORE_MAX / 4 ;
178  else
179  return AVPROBE_SCORE_MAX / 2;
180  }
181  return 0;
182 }
183 
184  static const AVClass class_gme = {
185  .class_name = "Game Music Emu demuxer",
186  .item_name = av_default_item_name,
187  .option = options,
188  .version = LIBAVUTIL_VERSION_INT,
189 };
190 
191  AVInputFormat ff_libgme_demuxer = {
192  .name = "libgme",
193  .long_name = NULL_IF_CONFIG_SMALL("Game Music Emu demuxer"),
194  .priv_data_size = sizeof(GMEContext),
195  .read_probe = probe_gme,
196  .read_header = read_header_gme,
197  .read_packet = read_packet_gme,
198  .read_close = read_close_gme,
199  .read_seek = read_seek_gme,
200  .priv_class = &class_gme,
201 };
NULL
#define NULL
Definition: coverity.c:32
AV_OPT_TYPE_INT64
Definition: opt.h:224
s
const char * s
Definition: avisynth_c.h:768
AVIOContext
Bytestream IO Context.
Definition: avio.h:161
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
avio_size
int64_t avio_size(AVIOContext *s)
Get the filesize.
Definition: aviobuf.c:336
AVOption
AVOption.
Definition: opt.h:246
OFFSET
#define OFFSET(x)
Definition: libgme.c:42
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
GMEContext
Definition: libgme.c:31
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
avpriv_set_pts_info
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:4820
AV_OPT_TYPE_INT
Definition: opt.h:223
options
static const AVOption options[]
Definition: libgme.c:45
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:153
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3884
AVPacket::size
int size
Definition: avcodec.h:1431
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:191
GMEContext::sample_rate
int sample_rate
Definition: libgme.c:38
read_packet_gme
static int read_packet_gme(AVFormatContext *s, AVPacket *pkt)
Definition: libgme.c:137
pkt
static AVPacket pkt
Definition: demuxing_decoding.c:54
A
#define A
Definition: libgme.c:43
probe_gme
static int probe_gme(AVProbeData *p)
Definition: libgme.c:172
read_header_gme
static int read_header_gme(AVFormatContext *s)
Definition: libgme.c:80
AVFormatContext
Format I/O context.
Definition: avformat.h:1342
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:72
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:31
opt.h
AVOptions.
AV_NE
#define AV_NE(be, le)
Definition: common.h:50
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4450
load_metadata
static int load_metadata(AVFormatContext *s)
Definition: libgme.c:58
AVPacket::data
uint8_t * data
Definition: avcodec.h:1430
D
#define D
Definition: libgme.c:44
flags
static int flags
Definition: log.c:55
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:55
read_close
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:145
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:648
av_new_packet
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:86
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
AVFormatContext::metadata
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1580
AVERROR
#define AVERROR(e)
Definition: error.h:43
GMEContext::music_emu
Music_Emu * music_emu
Definition: libgme.c:33
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:186
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3880
AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
add_meta
static void add_meta(AVFormatContext *s, const char *name, const char *value)
Definition: libgme.c:52
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:451
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:450
AVERROR_BUFFER_TOO_SMALL
#define AVERROR_BUFFER_TOO_SMALL
Buffer too small.
Definition: error.h:51
read_probe
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
value
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:109
GMEContext::info
gme_info_t * info
selected track
Definition: libgme.c:34
dummy
int dummy
Definition: motion.c:64
AV_CODEC_ID_PCM_S16BE
Definition: avcodec.h:453
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:530
AVStream
Stream structure.
Definition: avformat.h:873
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
sample_rate
sample_rate
Definition: ffmpeg_filter.c:190
AVFormatContext::pb
AVIOContext * pb
I/O context.
Definition: avformat.h:1384
buf
void * buf
Definition: avisynth_c.h:690
av_dict_set
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:70
GMEContext::max_size
int64_t max_size
Definition: libgme.c:39
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:67
snprintf
#define snprintf
Definition: snprintf.h:34
AUDIO_PKT_SIZE
#define AUDIO_PKT_SIZE
Definition: libgme.c:78
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:448
class_gme
static const AVClass class_gme
Definition: libgme.c:184
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:922
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: avcodec.h:3994
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:460
avformat.h
Main libavformat public API header.
ff_libgme_demuxer
AVInputFormat ff_libgme_demuxer
Definition: libgme.c:191
AV_CODEC_ID_PCM_S16LE
Definition: avcodec.h:452
AVERROR_UNKNOWN
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:71
AVFormatContext::priv_data
void * priv_data
Format private data.
Definition: avformat.h:1370
AVERROR_STREAM_NOT_FOUND
#define AVERROR_STREAM_NOT_FOUND
Stream not found.
Definition: error.h:65
GMEContext::track_index
int track_index
Definition: libgme.c:37
AVCodecParameters::channels
int channels
Audio only.
Definition: avcodec.h:3990
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:647
read_seek_gme
static int read_seek_gme(AVFormatContext *s, int stream_idx, int64_t ts, int flags)
Definition: libgme.c:164
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1020
AVERROR_EXTERNAL
#define AVERROR_EXTERNAL
Generic error in an external library.
Definition: error.h:57
AVPacket
This structure stores compressed data.
Definition: avcodec.h:1407
eval.h
simple arithmetic expression evaluator
name
const char * name
Definition: opengl_enc.c:103
read_close_gme
static int read_close_gme(AVFormatContext *s)
Definition: libgme.c:156
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