FFmpeg
nuv.c
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1 /*
2  * NuppelVideo decoder
3  * Copyright (c) 2006 Reimar Doeffinger
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 <stdio.h>
23 #include <stdlib.h>
24 #include <limits.h>
25 
26 #include "libavutil/bswap.h"
27 #include "libavutil/common.h"
28 #include "libavutil/intreadwrite.h"
29 #include "libavutil/lzo.h"
30 #include "libavutil/imgutils.h"
31 #include "avcodec.h"
32 #include "idctdsp.h"
33 #include "internal.h"
34 #include "rtjpeg.h"
35 
36 typedef struct NuvContext {
37  AVFrame *pic;
38  int codec_frameheader;
39  int quality;
40  int width, height;
41  unsigned int decomp_size;
42  unsigned char *decomp_buf;
43  uint32_t lq[64], cq[64];
44  RTJpegContext rtj;
45 } NuvContext;
46 
47 static const uint8_t fallback_lquant[] = {
48  16, 11, 10, 16, 24, 40, 51, 61,
49  12, 12, 14, 19, 26, 58, 60, 55,
50  14, 13, 16, 24, 40, 57, 69, 56,
51  14, 17, 22, 29, 51, 87, 80, 62,
52  18, 22, 37, 56, 68, 109, 103, 77,
53  24, 35, 55, 64, 81, 104, 113, 92,
54  49, 64, 78, 87, 103, 121, 120, 101,
55  72, 92, 95, 98, 112, 100, 103, 99
56 };
57 
58 static const uint8_t fallback_cquant[] = {
59  17, 18, 24, 47, 99, 99, 99, 99,
60  18, 21, 26, 66, 99, 99, 99, 99,
61  24, 26, 56, 99, 99, 99, 99, 99,
62  47, 66, 99, 99, 99, 99, 99, 99,
63  99, 99, 99, 99, 99, 99, 99, 99,
64  99, 99, 99, 99, 99, 99, 99, 99,
65  99, 99, 99, 99, 99, 99, 99, 99,
66  99, 99, 99, 99, 99, 99, 99, 99
67 };
68 
69 /**
70  * @brief copy frame data from buffer to AVFrame, handling stride.
71  * @param f destination AVFrame
72  * @param src source buffer, does not use any line-stride
73  * @param width width of the video frame
74  * @param height height of the video frame
75  */
76 static void copy_frame(AVFrame *f, const uint8_t *src, int width, int height)
77 {
78  uint8_t *src_data[4];
79  int src_linesize[4];
80  av_image_fill_arrays(src_data, src_linesize, src,
81  f->format, width, height, 1);
82  av_image_copy(f->data, f->linesize, (const uint8_t **)src_data, src_linesize,
83  f->format, width, height);
84 }
85 
86 /**
87  * @brief extract quantization tables from codec data into our context
88  */
89 static int get_quant(AVCodecContext *avctx, NuvContext *c, const uint8_t *buf,
90  int size)
91 {
92  int i;
93  if (size < 2 * 64 * 4) {
94  av_log(avctx, AV_LOG_ERROR, "insufficient rtjpeg quant data\n");
95  return AVERROR_INVALIDDATA;
96  }
97  for (i = 0; i < 64; i++, buf += 4)
98  c->lq[i] = AV_RL32(buf);
99  for (i = 0; i < 64; i++, buf += 4)
100  c->cq[i] = AV_RL32(buf);
101  return 0;
102 }
103 
104 /**
105  * @brief set quantization tables from a quality value
106  */
107 static void get_quant_quality(NuvContext *c, int quality)
108 {
109  int i;
110  quality = FFMAX(quality, 1);
111  for (i = 0; i < 64; i++) {
112  c->lq[i] = (fallback_lquant[i] << 7) / quality;
113  c->cq[i] = (fallback_cquant[i] << 7) / quality;
114  }
115 }
116 
117 static int codec_reinit(AVCodecContext *avctx, int width, int height,
118  int quality)
119 {
120  NuvContext *c = avctx->priv_data;
121  int ret;
122 
123  width = FFALIGN(width, 2);
124  height = FFALIGN(height, 2);
125  if (quality >= 0)
126  get_quant_quality(c, quality);
127  if (width != c->width || height != c->height) {
128  // also reserve space for a possible additional header
129  int64_t buf_size = height * (int64_t)width * 3 / 2
130  + FFMAX(AV_LZO_OUTPUT_PADDING, AV_INPUT_BUFFER_PADDING_SIZE)
131  + RTJPEG_HEADER_SIZE;
132  if (buf_size > INT_MAX/8)
133  return -1;
134  if ((ret = ff_set_dimensions(avctx, width, height)) < 0)
135  return ret;
136  c->width = width;
137  c->height = height;
138  av_fast_malloc(&c->decomp_buf, &c->decomp_size,
139  buf_size);
140  if (!c->decomp_buf) {
141  av_log(avctx, AV_LOG_ERROR,
142  "Can't allocate decompression buffer.\n");
143  return AVERROR(ENOMEM);
144  }
145  ff_rtjpeg_decode_init(&c->rtj, c->width, c->height, c->lq, c->cq);
146  av_frame_unref(c->pic);
147  return 1;
148  } else if (quality != c->quality)
149  ff_rtjpeg_decode_init(&c->rtj, c->width, c->height, c->lq, c->cq);
150 
151  return 0;
152 }
153 
154 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
155  AVPacket *avpkt)
156 {
157  const uint8_t *buf = avpkt->data;
158  int buf_size = avpkt->size;
159  NuvContext *c = avctx->priv_data;
160  AVFrame *picture = data;
161  int orig_size = buf_size;
162  int keyframe, ret;
163  int size_change = 0;
164  int minsize = 0;
165  int result, init_frame = !avctx->frame_number;
166  enum {
167  NUV_UNCOMPRESSED = '0',
168  NUV_RTJPEG = '1',
169  NUV_RTJPEG_IN_LZO = '2',
170  NUV_LZO = '3',
171  NUV_BLACK = 'N',
172  NUV_COPY_LAST = 'L'
173  } comptype;
174 
175  if (buf_size < 12) {
176  av_log(avctx, AV_LOG_ERROR, "coded frame too small\n");
177  return AVERROR_INVALIDDATA;
178  }
179 
180  // codec data (rtjpeg quant tables)
181  if (buf[0] == 'D' && buf[1] == 'R') {
182  int ret;
183  // Skip the rest of the frame header.
184  buf = &buf[12];
185  buf_size -= 12;
186  ret = get_quant(avctx, c, buf, buf_size);
187  if (ret < 0)
188  return ret;
189  ff_rtjpeg_decode_init(&c->rtj, c->width, c->height, c->lq, c->cq);
190  return orig_size;
191  }
192 
193  if (buf_size < 12 || buf[0] != 'V') {
194  av_log(avctx, AV_LOG_ERROR, "not a nuv video frame\n");
195  return AVERROR_INVALIDDATA;
196  }
197  comptype = buf[1];
198  switch (comptype) {
199  case NUV_RTJPEG_IN_LZO:
200  case NUV_RTJPEG:
201  keyframe = !buf[2];
202  if (c->width < 16 || c->height < 16) {
203  return AVERROR_INVALIDDATA;
204  }
205  break;
206  case NUV_COPY_LAST:
207  keyframe = 0;
208  break;
209  default:
210  keyframe = 1;
211  break;
212  }
213  switch (comptype) {
214  case NUV_UNCOMPRESSED:
215  minsize = c->width * c->height * 3 / 2;
216  break;
217  case NUV_RTJPEG:
218  minsize = c->width/16 * (c->height/16) * 6;
219  break;
220  case NUV_BLACK:
221  case NUV_COPY_LAST:
222  case NUV_LZO:
223  case NUV_RTJPEG_IN_LZO:
224  break;
225  default:
226  av_log(avctx, AV_LOG_ERROR, "unknown compression\n");
227  return AVERROR_INVALIDDATA;
228  }
229  if (buf_size < minsize / 4)
230  return AVERROR_INVALIDDATA;
231 retry:
232  // Skip the rest of the frame header.
233  buf = &buf[12];
234  buf_size -= 12;
235  if (comptype == NUV_RTJPEG_IN_LZO || comptype == NUV_LZO) {
236  int outlen = c->decomp_size - FFMAX(AV_INPUT_BUFFER_PADDING_SIZE, AV_LZO_OUTPUT_PADDING);
237  int inlen = buf_size;
238  if (av_lzo1x_decode(c->decomp_buf, &outlen, buf, &inlen)) {
239  av_log(avctx, AV_LOG_ERROR, "error during lzo decompression\n");
240  return AVERROR_INVALIDDATA;
241  }
242  buf = c->decomp_buf;
243  buf_size = c->decomp_size - FFMAX(AV_INPUT_BUFFER_PADDING_SIZE, AV_LZO_OUTPUT_PADDING) - outlen;
244  memset(c->decomp_buf + buf_size, 0, AV_INPUT_BUFFER_PADDING_SIZE);
245  }
246  if (c->codec_frameheader) {
247  int w, h, q;
248  if (buf_size < RTJPEG_HEADER_SIZE) {
249  av_log(avctx, AV_LOG_ERROR, "Too small NUV video frame\n");
250  return AVERROR_INVALIDDATA;
251  }
252  // There seem to exist two variants of this header: one starts with 'V'
253  // and 5 bytes unknown, the other matches current MythTV and is 4 bytes size,
254  // 1 byte header size (== 12), 1 byte version (== 0)
255  if (buf[0] != 'V' && AV_RL16(&buf[4]) != 0x000c) {
256  av_log(avctx, AV_LOG_ERROR, "Unknown secondary frame header (wrong codec_tag?)\n");
257  return AVERROR_INVALIDDATA;
258  }
259  w = AV_RL16(&buf[6]);
260  h = AV_RL16(&buf[8]);
261  q = buf[10];
262  if ((result = codec_reinit(avctx, w, h, q)) < 0)
263  return result;
264  if (result) {
265  buf = avpkt->data;
266  buf_size = avpkt->size;
267  size_change = 1;
268  goto retry;
269  }
270  buf = &buf[RTJPEG_HEADER_SIZE];
271  buf_size -= RTJPEG_HEADER_SIZE;
272  }
273 
274  if (size_change || keyframe) {
275  av_frame_unref(c->pic);
276  init_frame = 1;
277  }
278 
279  if ((result = ff_reget_buffer(avctx, c->pic)) < 0)
280  return result;
281  if (init_frame) {
282  memset(c->pic->data[0], 0, avctx->height * c->pic->linesize[0]);
283  memset(c->pic->data[1], 0x80, avctx->height * c->pic->linesize[1] / 2);
284  memset(c->pic->data[2], 0x80, avctx->height * c->pic->linesize[2] / 2);
285  }
286 
287  c->pic->pict_type = keyframe ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
288  c->pic->key_frame = keyframe;
289  // decompress/copy/whatever data
290  switch (comptype) {
291  case NUV_LZO:
292  case NUV_UNCOMPRESSED: {
293  int height = c->height;
294  if (buf_size < c->width * height * 3 / 2) {
295  av_log(avctx, AV_LOG_ERROR, "uncompressed frame too short\n");
296  height = buf_size / c->width / 3 * 2;
297  }
298  if(height > 0)
299  copy_frame(c->pic, buf, c->width, height);
300  break;
301  }
302  case NUV_RTJPEG_IN_LZO:
303  case NUV_RTJPEG:
304  ret = ff_rtjpeg_decode_frame_yuv420(&c->rtj, c->pic, buf, buf_size);
305  if (ret < 0)
306  return ret;
307  break;
308  case NUV_BLACK:
309  memset(c->pic->data[0], 0, c->width * c->height);
310  memset(c->pic->data[1], 128, c->width * c->height / 4);
311  memset(c->pic->data[2], 128, c->width * c->height / 4);
312  break;
313  case NUV_COPY_LAST:
314  /* nothing more to do here */
315  break;
316  }
317 
318  if ((result = av_frame_ref(picture, c->pic)) < 0)
319  return result;
320 
321  *got_frame = 1;
322  return orig_size;
323 }
324 
325 static av_cold int decode_init(AVCodecContext *avctx)
326 {
327  NuvContext *c = avctx->priv_data;
328  int ret;
329 
330  c->pic = av_frame_alloc();
331  if (!c->pic)
332  return AVERROR(ENOMEM);
333 
334  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
335  c->decomp_buf = NULL;
336  c->quality = -1;
337  c->width = 0;
338  c->height = 0;
339 
340  c->codec_frameheader = avctx->codec_tag == MKTAG('R', 'J', 'P', 'G');
341 
342  if (avctx->extradata_size)
343  get_quant(avctx, c, avctx->extradata, avctx->extradata_size);
344 
345  ff_rtjpeg_init(&c->rtj, avctx);
346 
347  if ((ret = codec_reinit(avctx, avctx->width, avctx->height, -1)) < 0)
348  return ret;
349 
350  return 0;
351 }
352 
353 static av_cold int decode_end(AVCodecContext *avctx)
354 {
355  NuvContext *c = avctx->priv_data;
356 
357  av_freep(&c->decomp_buf);
358  av_frame_free(&c->pic);
359 
360  return 0;
361 }
362 
363 AVCodec ff_nuv_decoder = {
364  .name = "nuv",
365  .long_name = NULL_IF_CONFIG_SMALL("NuppelVideo/RTJPEG"),
366  .type = AVMEDIA_TYPE_VIDEO,
367  .id = AV_CODEC_ID_NUV,
368  .priv_data_size = sizeof(NuvContext),
369  .init = decode_init,
370  .close = decode_end,
371  .decode = decode_frame,
372  .capabilities = AV_CODEC_CAP_DR1,
373  .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
374 };
AVCodec
AVCodec.
Definition: avcodec.h:3481
fallback_cquant
static const uint8_t fallback_cquant[]
Definition: nuv.c:58
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
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
NuvContext::codec_frameheader
int codec_frameheader
Definition: nuv.c:38
NuvContext::cq
uint32_t cq[64]
Definition: nuv.c:43
MKTAG
#define MKTAG(a, b, c, d)
Definition: common.h:366
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
copy_frame
static void copy_frame(AVFrame *f, const uint8_t *src, int width, int height)
copy frame data from buffer to AVFrame, handling stride.
Definition: nuv.c:76
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
w
uint8_t w
Definition: llviddspenc.c:38
NuvContext::width
int width
Definition: nuv.c:40
internal.h
AVPacket::data
uint8_t * data
Definition: avcodec.h:1477
data
const char data[16]
Definition: mxf.c:91
codec_reinit
static int codec_reinit(AVCodecContext *avctx, int width, int height, int quality)
Definition: nuv.c:117
ff_reget_buffer
int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame)
Identical in function to av_frame_make_writable(), except it uses ff_get_buffer() to allocate the buf...
Definition: decode.c:2012
quality
trying all byte sequences megabyte in length and selecting the best looking sequence will yield cases to try But a word about quality
Definition: rate_distortion.txt:12
ff_nuv_decoder
AVCodec ff_nuv_decoder
Definition: nuv.c:363
RTJPEG_HEADER_SIZE
#define RTJPEG_HEADER_SIZE
Definition: rtjpeg.h:31
NuvContext::quality
int quality
Definition: nuv.c:39
src
#define src
Definition: vp8dsp.c:254
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:189
ff_rtjpeg_decode_init
void ff_rtjpeg_decode_init(RTJpegContext *c, int width, int height, const uint32_t *lquant, const uint32_t *cquant)
initialize an RTJpegContext, may be called multiple times
Definition: rtjpeg.c:158
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
buf
void * buf
Definition: avisynth_c.h:766
av_cold
#define av_cold
Definition: attributes.h:84
decode
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:42
AVCodecContext::extradata_size
int extradata_size
Definition: avcodec.h:1667
width
#define width
intreadwrite.h
AV_CODEC_ID_NUV
@ AV_CODEC_ID_NUV
Definition: avcodec.h:302
NuvContext
Definition: nuv.c:36
get_quant
static int get_quant(AVCodecContext *avctx, NuvContext *c, const uint8_t *buf, int size)
extract quantization tables from codec data into our context
Definition: nuv.c:89
limits.h
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:90
NuvContext::decomp_buf
unsigned char * decomp_buf
Definition: nuv.c:42
AV_PIX_FMT_YUV420P
@ AV_PIX_FMT_YUV420P
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:66
f
#define f(width, name)
Definition: cbs_vp9.c:255
result
and forward the result(frame or status change) to the corresponding input. If nothing is possible
NULL
#define NULL
Definition: coverity.c:32
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:274
ff_rtjpeg_decode_frame_yuv420
int ff_rtjpeg_decode_frame_yuv420(RTJpegContext *c, AVFrame *f, const uint8_t *buf, int buf_size)
decode one rtjpeg YUV420 frame
Definition: rtjpeg.c:106
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
decode_end
static av_cold int decode_end(AVCodecContext *avctx)
Definition: nuv.c:353
av_lzo1x_decode
int av_lzo1x_decode(void *out, int *outlen, const void *in, int *inlen)
Decodes LZO 1x compressed data.
Definition: lzo.c:134
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:981
AVPacket::size
int size
Definition: avcodec.h:1478
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:188
av_image_fill_arrays
int av_image_fill_arrays(uint8_t *dst_data[4], int dst_linesize[4], const uint8_t *src, enum AVPixelFormat pix_fmt, int width, int height, int align)
Setup the data pointers and linesizes based on the specified image parameters and the provided array.
Definition: imgutils.c:411
av_frame_ref
int av_frame_ref(AVFrame *dst, const AVFrame *src)
Set up a new reference to the data described by the source frame.
Definition: frame.c:443
FFMAX
#define FFMAX(a, b)
Definition: common.h:94
size
int size
Definition: twinvq_data.h:11134
ff_rtjpeg_init
void ff_rtjpeg_init(RTJpegContext *c, AVCodecContext *avctx)
Definition: rtjpeg.c:170
get_quant_quality
static void get_quant_quality(NuvContext *c, int quality)
set quantization tables from a quality value
Definition: nuv.c:107
height
#define height
NuvContext::decomp_size
unsigned int decomp_size
Definition: nuv.c:41
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
AV_LZO_OUTPUT_PADDING
#define AV_LZO_OUTPUT_PADDING
Definition: lzo.h:47
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1666
FF_CODEC_CAP_INIT_CLEANUP
#define FF_CODEC_CAP_INIT_CLEANUP
The codec allows calling the close function for deallocation even if the init function returned a fai...
Definition: internal.h:48
common.h
uint8_t
uint8_t
Definition: audio_convert.c:194
av_frame_unref
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:553
AVCodec::name
const char * name
Name of the codec implementation.
Definition: avcodec.h:3488
AVCodecContext::height
int height
Definition: avcodec.h:1738
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1775
NuvContext::lq
uint32_t lq[64]
Definition: nuv.c:43
idctdsp.h
avcodec.h
ret
ret
Definition: filter_design.txt:187
bswap.h
NuvContext::pic
AVFrame * pic
Definition: nuv.c:37
lzo.h
AV_INPUT_BUFFER_PADDING_SIZE
#define AV_INPUT_BUFFER_PADDING_SIZE
Definition: avcodec.h:790
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:88
AVCodecContext
main external API structure.
Definition: avcodec.h:1565
av_image_copy
void av_image_copy(uint8_t *dst_data[4], int dst_linesizes[4], const uint8_t *src_data[4], const int src_linesizes[4], enum AVPixelFormat pix_fmt, int width, int height)
Copy image in src_data to dst_data.
Definition: imgutils.c:387
fallback_lquant
static const uint8_t fallback_lquant[]
Definition: nuv.c:47
rtjpeg.h
NuvContext::rtj
RTJpegContext rtj
Definition: nuv.c:44
init_frame
static void init_frame(FlacEncodeContext *s, int nb_samples)
Definition: flacenc.c:470
AV_PICTURE_TYPE_P
@ AV_PICTURE_TYPE_P
Predicted.
Definition: avutil.h:275
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
ff_set_dimensions
int ff_set_dimensions(AVCodecContext *s, int width, int height)
Check that the provided frame dimensions are valid and set them on the codec context.
Definition: utils.c:104
AVCodecContext::frame_number
int frame_number
Frame counter, set by libavcodec.
Definition: avcodec.h:2256
AVCodecContext::codec_tag
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:1590
FFALIGN
#define FFALIGN(x, a)
Definition: macros.h:48
AVPacket
This structure stores compressed data.
Definition: avcodec.h:1454
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:1592
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
av_fast_malloc
void av_fast_malloc(void *ptr, unsigned int *size, size_t min_size)
Allocate a buffer, reusing the given one if large enough.
Definition: mem.c:500
decode_init
static av_cold int decode_init(AVCodecContext *avctx)
Definition: nuv.c:325
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:1738
imgutils.h
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
NuvContext::height
int height
Definition: nuv.c:40
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
h
h
Definition: vp9dsp_template.c:2038
RTJpegContext
Definition: rtjpeg.h:33
decode_frame
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: nuv.c:154
Generated on Wed Aug 24 2022 21:26:53 for FFmpeg by   doxygen 1.8.17