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  av_packet_unref(pkt);
186  return AVERROR(ENOMEM);
187  }
188  memcpy(pal, gdv->pal, AVPALETTE_SIZE);
189  pkt->flags |= AV_PKT_FLAG_KEY;
190  gdv->is_first_video = 0;
191  }
192  }
193 
194  return 0;
195 }
196 
198  .name = "gdv",
199  .long_name = NULL_IF_CONFIG_SMALL("Gremlin Digital Video"),
200  .priv_data_size = sizeof(GDVContext),
204 };
Bytestream IO Context.
Definition: avio.h:161
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
Buffered I/O operations.
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:4929
const char * g
Definition: vf_curves.c:115
static int gdv_read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: gdv.c:155
AVInputFormat ff_gdv_demuxer
Definition: gdv.c:197
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3968
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:334
static AVPacket pkt
Format I/O context.
Definition: avformat.h:1358
int is_audio
Definition: gdv.c:30
uint8_t
int width
Video only.
Definition: avcodec.h:4034
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4502
#define AVERROR_EOF
End of file.
Definition: error.h:55
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:310
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1512
uint32_t pal[256]
Definition: gdv.c:35
#define U(x)
Definition: vp56_arith.h:37
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE bytes worth of palette...
Definition: avcodec.h:1193
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
const char * r
Definition: vf_curves.c:114
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3964
Definition: gdv.c:28
uint16_t width
Definition: gdv.c:47
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1486
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:641
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
#define b
Definition: input.c:41
AVFormatContext * ctx
Definition: movenc.c:48
int audio_stream_index
Definition: gdv.c:32
#define FF_ARRAY_ELEMS(a)
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:530
Stream structure.
Definition: avformat.h:881
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
static int gdv_read_probe(const AVProbeData *p)
Definition: gdv.c:37
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
uint16_t height
Definition: gdv.c:48
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:599
uint16_t id
Definition: gdv.c:46
int is_first_video
Definition: gdv.c:29
int video_stream_index
Definition: gdv.c:33
int error
contains the error code or 0 if no error happened
Definition: avio.h:245
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
static struct @266 FixedSize[]
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:930
int sample_rate
Audio only.
Definition: avcodec.h:4078
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:756
Main libavformat public API header.
static int gdv_read_header(AVFormatContext *ctx)
Definition: gdv.c:70
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:920
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:932
int audio_size
Definition: gdv.c:31
void * priv_data
Format private data.
Definition: avformat.h:1386
int channels
Audio only.
Definition: avcodec.h:4074
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:654
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:361
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: avcodec.h:3972
uint8_t * av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type, int size)
Allocate new information of a packet.
Definition: avpacket.c:329
int stream_index
Definition: avcodec.h:1482
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
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1457
PutByteContext pb
Definition: gdv.c:33