FFmpeg: libavformat/sierravmd.c Source File

FFmpeg
sierravmd.c
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1 /*
2  * Sierra VMD Format Demuxer
3  * Copyright (c) 2004 The FFmpeg project
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 /**
23  * @file
24  * Sierra VMD file demuxer
25  * by Vladimir "VAG" Gneushev (vagsoft at mail.ru)
26  * for more information on the Sierra VMD file format, visit:
27  * http://www.pcisys.net/~melanson/codecs/
28  */
29 
30 #include "libavutil/channel_layout.h"
31 #include "libavutil/intreadwrite.h"
32 #include "avformat.h"
33 #include "demux.h"
34 #include "internal.h"
35 #include "avio_internal.h"
36 
37  #define VMD_HEADER_SIZE 0x0330
38  #define BYTES_PER_FRAME_RECORD 16
39 
40  typedef struct vmd_frame {
41   int stream_index;
42   unsigned int frame_size;
43   int64_t frame_offset;
44   int64_t pts;
45   unsigned char frame_record[BYTES_PER_FRAME_RECORD];
46 } vmd_frame;
47 
48  typedef struct VmdDemuxContext {
49   int video_stream_index;
50   int audio_stream_index;
51 
52   unsigned int frame_count;
53   unsigned int frames_per_block;
54   vmd_frame *frame_table;
55   unsigned int current_frame;
56   int is_indeo3;
57 
58   int sample_rate;
59   int64_t audio_sample_counter;
60   int skiphdr;
61 
62   unsigned char vmd_header[VMD_HEADER_SIZE];
63 } VmdDemuxContext;
64 
65  static int vmd_probe(const AVProbeData *p)
66 {
67  int w, h, sample_rate;
68  if (p->buf_size < 806)
69  return 0;
70  /* check if the first 2 bytes of the file contain the appropriate size
71  * of a VMD header chunk */
72  if (AV_RL16(&p->buf[0]) != VMD_HEADER_SIZE - 2)
73  return 0;
74  w = AV_RL16(&p->buf[12]);
75  h = AV_RL16(&p->buf[14]);
76  sample_rate = AV_RL16(&p->buf[804]);
77  if ((!w || w > 2048 || !h || h > 2048) &&
78  sample_rate != 22050)
79  return 0;
80 
81  /* only return half certainty since this check is a bit sketchy */
82  return AVPROBE_SCORE_EXTENSION;
83 }
84 
85  static int vmd_read_header(AVFormatContext *s)
86 {
87  VmdDemuxContext *vmd = s->priv_data;
88  AVIOContext *pb = s->pb;
89  AVStream *st = NULL, *vst = NULL;
90  unsigned int toc_offset;
91  unsigned char *raw_frame_table;
92  int raw_frame_table_size;
93  int64_t current_offset;
94  int i, j, ret;
95  int width, height;
96  unsigned int total_frames;
97  int64_t current_audio_pts = 0;
98  unsigned char chunk[BYTES_PER_FRAME_RECORD];
99  int num, den;
100  int sound_buffers;
101 
102  /* fetch the main header, including the 2 header length bytes */
103  avio_seek(pb, 0, SEEK_SET);
104  if (avio_read(pb, vmd->vmd_header, VMD_HEADER_SIZE) != VMD_HEADER_SIZE)
105  return AVERROR(EIO);
106 
107  width = AV_RL16(&vmd->vmd_header[12]);
108  height = AV_RL16(&vmd->vmd_header[14]);
109  if (width && height) {
110  if(vmd->vmd_header[24] == 'i' && vmd->vmd_header[25] == 'v' && vmd->vmd_header[26] == '3') {
111  vmd->is_indeo3 = 1;
112  } else {
113  vmd->is_indeo3 = 0;
114  }
115  /* start up the decoders */
116  vst = avformat_new_stream(s, NULL);
117  if (!vst)
118  return AVERROR(ENOMEM);
119  avpriv_set_pts_info(vst, 33, 1, 10);
120  vmd->video_stream_index = vst->index;
121  vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
122  vst->codecpar->codec_id = vmd->is_indeo3 ? AV_CODEC_ID_INDEO3 : AV_CODEC_ID_VMDVIDEO;
123  vst->codecpar->codec_tag = 0; /* no fourcc */
124  vst->codecpar->width = width;
125  vst->codecpar->height = height;
126  if(vmd->is_indeo3 && vst->codecpar->width > 320){
127  vst->codecpar->width >>= 1;
128  vst->codecpar->height >>= 1;
129  }
130  if ((ret = ff_alloc_extradata(vst->codecpar, VMD_HEADER_SIZE)) < 0)
131  return ret;
132  memcpy(vst->codecpar->extradata, vmd->vmd_header, VMD_HEADER_SIZE);
133  }
134 
135  /* if sample rate is 0, assume no audio */
136  vmd->sample_rate = AV_RL16(&vmd->vmd_header[804]);
137  if (vmd->sample_rate) {
138  int channels;
139  st = avformat_new_stream(s, NULL);
140  if (!st)
141  return AVERROR(ENOMEM);
142  vmd->audio_stream_index = st->index;
143  st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
144  st->codecpar->codec_id = AV_CODEC_ID_VMDAUDIO;
145  st->codecpar->codec_tag = 0; /* no fourcc */
146  st->codecpar->sample_rate = vmd->sample_rate;
147  st->codecpar->block_align = AV_RL16(&vmd->vmd_header[806]);
148  if (st->codecpar->block_align & 0x8000) {
149  st->codecpar->bits_per_coded_sample = 16;
150  st->codecpar->block_align = -(st->codecpar->block_align - 0x10000);
151  } else {
152  st->codecpar->bits_per_coded_sample = 8;
153  }
154  if (vmd->vmd_header[811] & 0x80) {
155  channels = 2;
156  } else if (vmd->vmd_header[811] & 0x2) {
157  /* Shivers 2 stereo audio */
158  /* Frame length is for 1 channel */
159  channels = 2;
160  st->codecpar->block_align = st->codecpar->block_align << 1;
161  } else {
162  channels = 1;
163  }
164  av_channel_layout_default(&st->codecpar->ch_layout, channels);
165  st->codecpar->bit_rate = st->codecpar->sample_rate *
166  st->codecpar->bits_per_coded_sample * channels;
167 
168  /* calculate pts */
169  num = st->codecpar->block_align;
170  den = st->codecpar->sample_rate * channels;
171  av_reduce(&num, &den, num, den, (1UL<<31)-1);
172  if (vst)
173  avpriv_set_pts_info(vst, 33, num, den);
174  avpriv_set_pts_info(st, 33, num, den);
175  }
176  if (!s->nb_streams)
177  return AVERROR_INVALIDDATA;
178 
179  toc_offset = AV_RL32(&vmd->vmd_header[812]);
180  vmd->frame_count = AV_RL16(&vmd->vmd_header[6]);
181  vmd->frames_per_block = AV_RL16(&vmd->vmd_header[18]);
182  avio_seek(pb, toc_offset, SEEK_SET);
183 
184  raw_frame_table = NULL;
185  vmd->frame_table = NULL;
186  sound_buffers = AV_RL16(&vmd->vmd_header[808]);
187  raw_frame_table_size = vmd->frame_count * 6;
188  raw_frame_table = av_malloc(raw_frame_table_size);
189  vmd->frame_table = av_malloc_array(vmd->frame_count * vmd->frames_per_block + sound_buffers, sizeof(vmd_frame));
190  if (!raw_frame_table || !vmd->frame_table) {
191  ret = AVERROR(ENOMEM);
192  goto error;
193  }
194  if (avio_read(pb, raw_frame_table, raw_frame_table_size) !=
195  raw_frame_table_size) {
196  ret = AVERROR(EIO);
197  goto error;
198  }
199 
200  total_frames = 0;
201  for (i = 0; i < vmd->frame_count; i++) {
202 
203  current_offset = AV_RL32(&raw_frame_table[6 * i + 2]);
204 
205  /* handle each entry in index block */
206  for (j = 0; j < vmd->frames_per_block; j++) {
207  int type;
208  uint32_t size;
209 
210  if ((ret = avio_read(pb, chunk, BYTES_PER_FRAME_RECORD)) != BYTES_PER_FRAME_RECORD) {
211  av_log(s, AV_LOG_ERROR, "Failed to read frame record\n");
212  if (ret >= 0)
213  ret = AVERROR_INVALIDDATA;
214  goto error;
215  }
216  type = chunk[0];
217  size = AV_RL32(&chunk[2]);
218  if (size > INT_MAX / 2) {
219  av_log(s, AV_LOG_ERROR, "Invalid frame size\n");
220  ret = AVERROR_INVALIDDATA;
221  goto error;
222  }
223  if(!size && type != 1)
224  continue;
225  switch(type) {
226  case 1: /* Audio Chunk */
227  if (!st) break;
228  /* first audio chunk contains several audio buffers */
229  vmd->frame_table[total_frames].frame_offset = current_offset;
230  vmd->frame_table[total_frames].stream_index = vmd->audio_stream_index;
231  vmd->frame_table[total_frames].frame_size = size;
232  memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
233  vmd->frame_table[total_frames].pts = current_audio_pts;
234  total_frames++;
235  if(!current_audio_pts)
236  current_audio_pts += sound_buffers - 1;
237  else
238  current_audio_pts++;
239  break;
240  case 2: /* Video Chunk */
241  if (!vst)
242  break;
243  vmd->frame_table[total_frames].frame_offset = current_offset;
244  vmd->frame_table[total_frames].stream_index = vmd->video_stream_index;
245  vmd->frame_table[total_frames].frame_size = size;
246  memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
247  vmd->frame_table[total_frames].pts = i;
248  total_frames++;
249  break;
250  }
251  current_offset += size;
252  }
253  }
254 
255 
256  vmd->current_frame = 0;
257  vmd->frame_count = total_frames;
258 
259  ret = 0;
260 error:
261  av_freep(&raw_frame_table);
262  return ret;
263 }
264 
265  static int vmd_read_packet(AVFormatContext *s,
266  AVPacket *pkt)
267 {
268  VmdDemuxContext *vmd = s->priv_data;
269  AVIOContext *pb = s->pb;
270  int ret = 0;
271  vmd_frame *frame;
272 
273  if (vmd->current_frame >= vmd->frame_count)
274  return AVERROR_EOF;
275 
276  frame = &vmd->frame_table[vmd->current_frame];
277  /* position the stream (will probably be there already) */
278  avio_seek(pb, frame->frame_offset, SEEK_SET);
279 
280  if(ffio_limit(pb, frame->frame_size) != frame->frame_size)
281  return AVERROR(EIO);
282  ret = av_new_packet(pkt, frame->frame_size + BYTES_PER_FRAME_RECORD);
283  if (ret < 0)
284  return ret;
285  pkt->pos= avio_tell(pb);
286  memcpy(pkt->data, frame->frame_record, BYTES_PER_FRAME_RECORD);
287  if(vmd->is_indeo3 && frame->frame_record[0] == 0x02)
288  ret = avio_read(pb, pkt->data, frame->frame_size);
289  else
290  ret = avio_read(pb, pkt->data + BYTES_PER_FRAME_RECORD,
291  frame->frame_size);
292 
293  if (ret != frame->frame_size) {
294  ret = AVERROR(EIO);
295  }
296  pkt->stream_index = frame->stream_index;
297  pkt->pts = frame->pts;
298  av_log(s, AV_LOG_DEBUG, " dispatching %s frame with %d bytes and pts %"PRId64"\n",
299  (frame->frame_record[0] == 0x02) ? "video" : "audio",
300  frame->frame_size + BYTES_PER_FRAME_RECORD,
301  pkt->pts);
302 
303  vmd->current_frame++;
304 
305  return ret;
306 }
307 
308  static int vmd_read_close(AVFormatContext *s)
309 {
310  VmdDemuxContext *vmd = s->priv_data;
311 
312  av_freep(&vmd->frame_table);
313 
314  return 0;
315 }
316 
317  const FFInputFormat ff_vmd_demuxer = {
318  .p.name = "vmd",
319  .p.long_name = NULL_IF_CONFIG_SMALL("Sierra VMD"),
320  .priv_data_size = sizeof(VmdDemuxContext),
321  .flags_internal = FF_INFMT_FLAG_INIT_CLEANUP,
322  .read_probe = vmd_probe,
323  .read_header = vmd_read_header,
324  .read_packet = vmd_read_packet,
325  .read_close = vmd_read_close,
326 };
error
static void error(const char *err)
Definition: target_bsf_fuzzer.c:31
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
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
VMD_HEADER_SIZE
#define VMD_HEADER_SIZE
Definition: sierravmd.c:37
vmd_frame
Definition: sierravmd.c:40
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
int64_t
long long int64_t
Definition: coverity.c:34
vmd_read_close
static int vmd_read_close(AVFormatContext *s)
Definition: sierravmd.c:308
AVFrame::pts
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:456
w
uint8_t w
Definition: llviddspenc.c:38
AV_CODEC_ID_INDEO3
@ AV_CODEC_ID_INDEO3
Definition: codec_id.h:80
AVPacket::data
uint8_t * data
Definition: packet.h:522
VmdDemuxContext::frame_count
unsigned int frame_count
Definition: sierravmd.c:52
VmdDemuxContext::frames_per_block
unsigned int frames_per_block
Definition: sierravmd.c:53
AVCodecParameters::codec_tag
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:59
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:454
sample_rate
sample_rate
Definition: ffmpeg_filter.c:409
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:30
ff_vmd_demuxer
const FFInputFormat ff_vmd_demuxer
Definition: sierravmd.c:317
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:853
vmd_frame::stream_index
int stream_index
Definition: sierravmd.c:41
read_close
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:143
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:494
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
av_reduce
int av_reduce(int *dst_num, int *dst_den, int64_t num, int64_t den, int64_t max)
Reduce a fraction.
Definition: rational.c:35
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
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_read_callback.c:41
VmdDemuxContext::is_indeo3
int is_indeo3
Definition: sierravmd.c:56
VmdDemuxContext::current_frame
unsigned int current_frame
Definition: sierravmd.c:55
width
#define width
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:198
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:98
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:553
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:453
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AV_CODEC_ID_VMDAUDIO
@ AV_CODEC_ID_VMDAUDIO
Definition: codec_id.h:451
AV_LOG_DEBUG
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:201
channels
channels
Definition: aptx.h:31
AV_RL16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:94
VmdDemuxContext::frame_table
vmd_frame * frame_table
Definition: sierravmd.c:54
vmd_probe
static int vmd_probe(const AVProbeData *p)
Definition: sierravmd.c:65
VmdDemuxContext::vmd_header
unsigned char vmd_header[VMD_HEADER_SIZE]
Definition: sierravmd.c:62
frame
static AVFrame * frame
Definition: demux_decode.c:54
FF_INFMT_FLAG_INIT_CLEANUP
#define FF_INFMT_FLAG_INIT_CLEANUP
For an FFInputFormat with this flag set read_close() needs to be called by the caller upon read_heade...
Definition: demux.h:35
AVFormatContext
Format I/O context.
Definition: avformat.h:1255
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:766
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:550
NULL
#define NULL
Definition: coverity.c:32
VmdDemuxContext::skiphdr
int skiphdr
Definition: sierravmd.c:60
VmdDemuxContext::video_stream_index
int video_stream_index
Definition: sierravmd.c:49
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:451
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:180
AV_CODEC_ID_VMDVIDEO
@ AV_CODEC_ID_VMDVIDEO
Definition: codec_id.h:104
VmdDemuxContext::sample_rate
int sample_rate
Definition: sierravmd.c:58
AVPROBE_SCORE_EXTENSION
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:461
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:184
AVIOContext
Bytestream IO Context.
Definition: avio.h:160
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:106
vmd_read_header
static int vmd_read_header(AVFormatContext *s)
Definition: sierravmd.c:85
size
int size
Definition: twinvq_data.h:10344
FFInputFormat::p
AVInputFormat p
The public AVInputFormat.
Definition: demux.h:41
height
#define height
ffio_limit
int ffio_limit(AVIOContext *s, int size)
Definition: aviobuf.c:1060
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:830
vmd_frame::pts
int64_t pts
Definition: sierravmd.c:44
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:515
avio_internal.h
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:191
av_malloc_array
#define av_malloc_array(a, b)
Definition: tableprint_vlc.h:31
vmd_read_packet
static int vmd_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: sierravmd.c:265
demux.h
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:743
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:230
avformat.h
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
VmdDemuxContext
Definition: sierravmd.c:48
AVStream::index
int index
stream index in AVFormatContext
Definition: avformat.h:749
channel_layout.h
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:611
BYTES_PER_FRAME_RECORD
#define BYTES_PER_FRAME_RECORD
Definition: sierravmd.c:38
VmdDemuxContext::audio_stream_index
int audio_stream_index
Definition: sierravmd.c:50
AVPacket::stream_index
int stream_index
Definition: packet.h:524
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:30
vmd_frame::frame_size
unsigned int frame_size
Definition: sierravmd.c:42
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:110
VmdDemuxContext::audio_sample_counter
int64_t audio_sample_counter
Definition: sierravmd.c:59
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
AVPacket
This structure stores compressed data.
Definition: packet.h:499
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:542
FFInputFormat
Definition: demux.h:37
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:97
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
h
h
Definition: vp9dsp_template.c:2038
vmd_frame::frame_offset
int64_t frame_offset
Definition: sierravmd.c:43
vmd_frame::frame_record
unsigned char frame_record[BYTES_PER_FRAME_RECORD]
Definition: sierravmd.c:45
ff_alloc_extradata
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:239
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