FFmpeg
gdv.c
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1 /*
2  * Gremlin Digital Video demuxer
3  * Copyright (c) 2017 Paul B Mahol
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 #include "libavutil/intreadwrite.h"
23 
24 #include "avformat.h"
25 #include "avio.h"
26 #include "internal.h"
27 
28 typedef struct GDVContext {
30  int is_audio;
34  unsigned pal[256];
35 } GDVContext;
36 
37 static int gdv_read_probe(const AVProbeData *p)
38 {
39  if (AV_RL32(p->buf) == 0x29111994)
40  return AVPROBE_SCORE_MAX;
41 
42  return 0;
43 }
44 
45 static struct {
46  uint16_t id;
47  uint16_t width;
48  uint16_t height;
49 } FixedSize[] = {
50  { 0, 320, 200},
51  { 1, 640, 200},
52  { 2, 320, 167},
53  { 3, 320, 180},
54  { 4, 320, 400},
55  { 5, 320, 170},
56  { 6, 160, 85},
57  { 7, 160, 83},
58  { 8, 160, 90},
59  { 9, 280, 128},
60  {10, 320, 240},
61  {11, 320, 201},
62  {16, 640, 400},
63  {17, 640, 200},
64  {18, 640, 180},
65  {19, 640, 167},
66  {20, 640, 170},
67  {21, 320, 240}
68 };
69 
71 {
72  GDVContext *gdv = ctx->priv_data;
73  AVIOContext *pb = ctx->pb;
74  AVStream *vst, *ast;
75  unsigned fps, snd_flags, vid_depth, size_id;
76 
77  avio_skip(pb, 4);
78  size_id = avio_rl16(pb);
79 
80  vst = avformat_new_stream(ctx, 0);
81  if (!vst)
82  return AVERROR(ENOMEM);
83 
84  vst->start_time = 0;
85  vst->duration =
86  vst->nb_frames = avio_rl16(pb);
87 
88  fps = avio_rl16(pb);
89  if (!fps)
90  return AVERROR_INVALIDDATA;
91 
92  snd_flags = avio_rl16(pb);
93  if (snd_flags & 1) {
94  ast = avformat_new_stream(ctx, 0);
95  if (!ast)
96  return AVERROR(ENOMEM);
97 
98  ast->start_time = 0;
100  ast->codecpar->codec_tag = 0;
101  ast->codecpar->sample_rate = avio_rl16(pb);
102  ast->codecpar->channels = 1 + !!(snd_flags & 2);
103  if (snd_flags & 8) {
105  } else {
106  ast->codecpar->codec_id = (snd_flags & 4) ? AV_CODEC_ID_PCM_S16LE : AV_CODEC_ID_PCM_U8;
107  }
108 
109  avpriv_set_pts_info(ast, 64, 1, ast->codecpar->sample_rate);
110  gdv->audio_size = (ast->codecpar->sample_rate / fps) *
111  ast->codecpar->channels * (1 + !!(snd_flags & 4)) / (1 + !!(snd_flags & 8));
112  gdv->is_audio = 1;
113  } else {
114  avio_skip(pb, 2);
115  }
116  vid_depth = avio_rl16(pb);
117  avio_skip(pb, 4);
118 
121  vst->codecpar->codec_tag = 0;
122  vst->codecpar->width = avio_rl16(pb);
123  vst->codecpar->height = avio_rl16(pb);
124 
125  if (vst->codecpar->width == 0 || vst->codecpar->height == 0) {
126  int i;
127 
128  for (i = 0; i < FF_ARRAY_ELEMS(FixedSize) - 1; i++) {
129  if (FixedSize[i].id == size_id)
130  break;
131  }
132 
133  vst->codecpar->width = FixedSize[i].width;
134  vst->codecpar->height = FixedSize[i].height;
135  }
136 
137  avpriv_set_pts_info(vst, 64, 1, fps);
138 
139  if (vid_depth & 1) {
140  int i;
141 
142  for (i = 0; i < 256; i++) {
143  unsigned r = avio_r8(pb);
144  unsigned g = avio_r8(pb);
145  unsigned b = avio_r8(pb);
146  gdv->pal[i] = 0xFFU << 24 | r << 18 | g << 10 | b << 2;
147  }
148  }
149 
150  gdv->is_first_video = 1;
151 
152  return 0;
153 }
154 
156 {
157  GDVContext *gdv = ctx->priv_data;
158  AVIOContext *pb = ctx->pb;
159  int ret;
160 
161  if (avio_feof(pb))
162  return pb->error ? pb->error : AVERROR_EOF;
163 
164  if (gdv->audio_size && gdv->is_audio) {
165  ret = av_get_packet(pb, pkt, gdv->audio_size);
166  if (ret < 0)
167  return ret;
168  pkt->stream_index = 1;
169  gdv->is_audio = 0;
170  } else {
171  uint8_t *pal;
172 
173  if (avio_rl16(pb) != 0x1305)
174  return AVERROR_INVALIDDATA;
175  ret = av_get_packet(pb, pkt, 4 + avio_rl16(pb));
176  if (ret < 0)
177  return ret;
178  pkt->stream_index = 0;
179  gdv->is_audio = 1;
180 
181  if (gdv->is_first_video) {
184  if (!pal) {
185  return AVERROR(ENOMEM);
186  }
187  memcpy(pal, gdv->pal, AVPALETTE_SIZE);
189  gdv->is_first_video = 0;
190  }
191  }
192 
193  return 0;
194 }
195 
197  .name = "gdv",
198  .long_name = NULL_IF_CONFIG_SMALL("Gremlin Digital Video"),
199  .priv_data_size = sizeof(GDVContext),
203 };
AV_CODEC_ID_PCM_S16LE
@ AV_CODEC_ID_PCM_S16LE
Definition: codec_id.h:313
r
const char * r
Definition: vf_curves.c:116
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:4375
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
b
#define b
Definition: input.c:40
AV_PKT_DATA_PALETTE
@ AV_PKT_DATA_PALETTE
An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE bytes worth of palette.
Definition: packet.h:46
AVIOContext::error
int error
contains the error code or 0 if no error happened
Definition: avio.h:245
AV_CODEC_ID_GDV
@ AV_CODEC_ID_GDV
Definition: codec_id.h:284
AVCodecParameters::codec_tag
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:64
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:404
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
AVCodecParameters::channels
int channels
Audio only.
Definition: codec_par.h:166
U
#define U(x)
Definition: vp56_arith.h:37
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:890
avio_rl16
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:717
pkt
AVPacket * pkt
Definition: movenc.c:59
AVInputFormat
Definition: avformat.h:626
FF_ARRAY_ELEMS
#define FF_ARRAY_ELEMS(a)
Definition: sinewin_tablegen.c:29
gdv_read_probe
static int gdv_read_probe(const AVProbeData *p)
Definition: gdv.c:37
intreadwrite.h
id
uint16_t id
Definition: gdv.c:46
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:631
g
const char * g
Definition: vf_curves.c:117
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
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:126
GDVContext::audio_size
int audio_size
Definition: gdv.c:31
ctx
AVFormatContext * ctx
Definition: movenc.c:48
AVFormatContext
Format I/O context.
Definition: avformat.h:1107
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:994
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:527
GDVContext::is_audio
int is_audio
Definition: gdv.c:30
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
AVPALETTE_SIZE
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
AVFormatContext::pb
AVIOContext * pb
I/O context.
Definition: avformat.h:1149
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:170
AVStream::nb_frames
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:892
GDVContext::audio_stream_index
int audio_stream_index
Definition: gdv.c:32
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:116
GDVContext::is_first_video
int is_first_video
Definition: gdv.c:29
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:4800
ff_gdv_demuxer
const AVInputFormat ff_gdv_demuxer
Definition: gdv.c:196
avio.h
gdv_read_header
static int gdv_read_header(AVFormatContext *ctx)
Definition: gdv.c:70
GDVContext
Definition: gdv.c:29
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:607
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:379
height
uint16_t height
Definition: gdv.c:48
i
int i
Definition: input.c:406
width
uint16_t width
Definition: gdv.c:47
FixedSize
static struct @252 FixedSize[]
AVCodecParameters::height
int height
Definition: codec_par.h:127
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:282
GDVContext::pal
uint32_t pal[256]
Definition: gdv.c:36
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:847
avformat.h
GDVContext::video_stream_index
int video_stream_index
Definition: gdv.c:33
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
av_packet_new_side_data
uint8_t * av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type, size_t size)
Allocate new information of a packet.
Definition: avpacket.c:220
AVPacket::stream_index
int stream_index
Definition: packet.h:375
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:327
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AV_CODEC_ID_PCM_U8
@ AV_CODEC_ID_PCM_U8
Definition: codec_id.h:318
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
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
AVStream::start_time
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:880
AVFormatContext::priv_data
void * priv_data
Format private data.
Definition: avformat.h:1135
AV_CODEC_ID_GREMLIN_DPCM
@ AV_CODEC_ID_GREMLIN_DPCM
Definition: codec_id.h:418
gdv_read_packet
static int gdv_read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: gdv.c:155
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:354