FFmpeg
lscrdec.c
Go to the documentation of this file.
1 /*
2  * Copyright (c) 2019 Paul B Mahol
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include <stdint.h>
22 #include <zlib.h>
23 
24 #include "libavutil/frame.h"
25 #include "libavutil/error.h"
26 #include "libavutil/log.h"
27 
28 #include "avcodec.h"
29 #include "bytestream.h"
30 #include "codec.h"
31 #include "codec_internal.h"
32 #include "internal.h"
33 #include "packet.h"
34 #include "png.h"
35 #include "pngdsp.h"
36 #include "zlib_wrapper.h"
37 
38 typedef struct LSCRContext {
41 
43  uint8_t *buffer;
45  uint8_t *crow_buf;
46  int crow_size;
47  uint8_t *last_row;
48  unsigned int last_row_size;
49 
51  uint8_t *image_buf;
53  int row_size;
54  int cur_h;
55  int y;
56 
58 } LSCRContext;
59 
60 static void handle_row(LSCRContext *s)
61 {
62  uint8_t *ptr, *last_row;
63 
64  ptr = s->image_buf + s->image_linesize * s->y;
65  if (s->y == 0)
66  last_row = s->last_row;
67  else
68  last_row = ptr - s->image_linesize;
69 
70  ff_png_filter_row(&s->dsp, ptr, s->crow_buf[0], s->crow_buf + 1,
71  last_row, s->row_size, 3);
72 
73  s->y++;
74 }
75 
76 static int decode_idat(LSCRContext *s, z_stream *zstream, int length)
77 {
78  int ret;
79  zstream->avail_in = FFMIN(length, bytestream2_get_bytes_left(&s->gb));
80  zstream->next_in = s->gb.buffer;
81 
82  if (length <= 0)
83  return AVERROR_INVALIDDATA;
84 
85  bytestream2_skip(&s->gb, length);
86 
87  /* decode one line if possible */
88  while (zstream->avail_in > 0) {
89  ret = inflate(zstream, Z_PARTIAL_FLUSH);
90  if (ret != Z_OK && ret != Z_STREAM_END) {
91  av_log(s->avctx, AV_LOG_ERROR, "inflate returned error %d\n", ret);
92  return AVERROR_EXTERNAL;
93  }
94  if (zstream->avail_out == 0) {
95  if (s->y < s->cur_h) {
96  handle_row(s);
97  }
98  zstream->avail_out = s->crow_size;
99  zstream->next_out = s->crow_buf;
100  }
101  if (ret == Z_STREAM_END && zstream->avail_in > 0) {
102  av_log(s->avctx, AV_LOG_WARNING,
103  "%d undecompressed bytes left in buffer\n", zstream->avail_in);
104  return 0;
105  }
106  }
107  return 0;
108 }
109 
110 static int decode_frame_lscr(AVCodecContext *avctx, AVFrame *rframe,
111  int *got_frame, AVPacket *avpkt)
112 {
113  LSCRContext *const s = avctx->priv_data;
114  GetByteContext *gb = &s->gb;
115  AVFrame *frame = s->last_picture;
116  int ret, nb_blocks, offset = 0;
117 
118  if (avpkt->size < 2)
119  return AVERROR_INVALIDDATA;
120  if (avpkt->size == 2)
121  return 0;
122 
123  bytestream2_init(gb, avpkt->data, avpkt->size);
124 
125  nb_blocks = bytestream2_get_le16(gb);
126  if (bytestream2_get_bytes_left(gb) < 2 + nb_blocks * (12 + 8))
127  return AVERROR_INVALIDDATA;
128 
129  ret = ff_reget_buffer(avctx, frame,
130  nb_blocks ? 0 : FF_REGET_BUFFER_FLAG_READONLY);
131  if (ret < 0)
132  return ret;
133 
134  for (int b = 0; b < nb_blocks; b++) {
135  z_stream *const zstream = &s->zstream.zstream;
136  int x, y, x2, y2, w, h, left;
137  uint32_t csize, size;
138 
139  if (inflateReset(zstream) != Z_OK)
140  return AVERROR_EXTERNAL;
141 
142  bytestream2_seek(gb, 2 + b * 12, SEEK_SET);
143 
144  x = bytestream2_get_le16(gb);
145  y = bytestream2_get_le16(gb);
146  x2 = bytestream2_get_le16(gb);
147  y2 = bytestream2_get_le16(gb);
148  w = x2-x;
149  s->cur_h = h = y2-y;
150 
151  if (w <= 0 || x < 0 || x >= avctx->width || w + x > avctx->width ||
152  h <= 0 || y < 0 || y >= avctx->height || h + y > avctx->height)
153  return AVERROR_INVALIDDATA;
154 
155  size = bytestream2_get_le32(gb);
156 
157  frame->key_frame = (nb_blocks == 1) &&
158  (w == avctx->width) &&
159  (h == avctx->height) &&
160  (x == 0) && (y == 0);
161 
162  bytestream2_seek(gb, 2 + nb_blocks * 12 + offset, SEEK_SET);
163  csize = bytestream2_get_be32(gb);
164  if (bytestream2_get_le32(gb) != MKTAG('I', 'D', 'A', 'T'))
165  return AVERROR_INVALIDDATA;
166 
167  offset += size;
168  left = size;
169 
170  s->y = 0;
171  s->row_size = w * 3;
172 
173  av_fast_padded_malloc(&s->buffer, &s->buffer_size, s->row_size + 16);
174  if (!s->buffer)
175  return AVERROR(ENOMEM);
176 
177  av_fast_padded_malloc(&s->last_row, &s->last_row_size, s->row_size);
178  if (!s->last_row)
179  return AVERROR(ENOMEM);
180 
181  s->crow_size = w * 3 + 1;
182  s->crow_buf = s->buffer + 15;
183  zstream->avail_out = s->crow_size;
184  zstream->next_out = s->crow_buf;
185  s->image_buf = frame->data[0] + (avctx->height - y - 1) * frame->linesize[0] + x * 3;
186  s->image_linesize =-frame->linesize[0];
187 
188  while (left > 16) {
189  ret = decode_idat(s, zstream, csize);
190  if (ret < 0)
191  return ret;
192  left -= csize + 16;
193  if (left > 16) {
194  bytestream2_skip(gb, 4);
195  csize = bytestream2_get_be32(gb);
196  if (bytestream2_get_le32(gb) != MKTAG('I', 'D', 'A', 'T'))
197  return AVERROR_INVALIDDATA;
198  }
199  }
200  }
201 
202  frame->pict_type = frame->key_frame ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
203 
204  if ((ret = av_frame_ref(rframe, frame)) < 0)
205  return ret;
206 
207  *got_frame = 1;
208 
209  return avpkt->size;
210 }
211 
213 {
214  LSCRContext *s = avctx->priv_data;
215 
216  av_frame_free(&s->last_picture);
217  av_freep(&s->buffer);
218  av_freep(&s->last_row);
219  ff_inflate_end(&s->zstream);
220 
221  return 0;
222 }
223 
225 {
226  LSCRContext *s = avctx->priv_data;
227 
228  avctx->color_range = AVCOL_RANGE_JPEG;
229  avctx->pix_fmt = AV_PIX_FMT_BGR24;
230 
231  s->avctx = avctx;
232  s->last_picture = av_frame_alloc();
233  if (!s->last_picture)
234  return AVERROR(ENOMEM);
235 
236  ff_pngdsp_init(&s->dsp);
237 
238  return ff_inflate_init(&s->zstream, avctx);
239 }
240 
242 {
243  LSCRContext *s = avctx->priv_data;
244  av_frame_unref(s->last_picture);
245 }
246 
248  .p.name = "lscr",
249  .p.long_name = NULL_IF_CONFIG_SMALL("LEAD Screen Capture"),
250  .p.type = AVMEDIA_TYPE_VIDEO,
251  .p.id = AV_CODEC_ID_LSCR,
252  .p.capabilities = AV_CODEC_CAP_DR1,
253  .priv_data_size = sizeof(LSCRContext),
255  .close = lscr_decode_close,
257  .flush = lscr_decode_flush,
258  .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
259 };
handle_row
static void handle_row(LSCRContext *s)
Definition: lscrdec.c:60
PNGDSPContext
Definition: pngdsp.h:27
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
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: codec_internal.h:41
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
GetByteContext
Definition: bytestream.h:33
lscr_decode_close
static int lscr_decode_close(AVCodecContext *avctx)
Definition: lscrdec.c:212
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:116
LSCRContext::last_row
uint8_t * last_row
Definition: lscrdec.c:47
bytestream2_seek
static av_always_inline int bytestream2_seek(GetByteContext *g, int offset, int whence)
Definition: bytestream.h:212
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:325
w
uint8_t w
Definition: llviddspenc.c:38
AVCOL_RANGE_JPEG
@ AVCOL_RANGE_JPEG
Full range content.
Definition: pixfmt.h:601
internal.h
AVPacket::data
uint8_t * data
Definition: packet.h:374
b
#define b
Definition: input.c:34
FFCodec
Definition: codec_internal.h:118
AV_PIX_FMT_BGR24
@ AV_PIX_FMT_BGR24
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:69
init
static int init
Definition: av_tx.c:47
LSCRContext::last_picture
AVFrame * last_picture
Definition: lscrdec.c:42
bytestream2_skip
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:168
LSCRContext::last_row_size
unsigned int last_row_size
Definition: lscrdec.c:48
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:122
inflate
static void inflate(uint8_t *dst, const uint8_t *p1, int width, int threshold, const uint8_t *coordinates[], int coord, int maxc)
Definition: vf_neighbor.c:195
LSCRContext::dsp
PNGDSPContext dsp
Definition: lscrdec.c:39
codec.h
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:104
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
pngdsp.h
zlib_wrapper.h
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:260
s
#define s(width, name)
Definition: cbs_vp9.c:256
LSCRContext
Definition: lscrdec.c:38
LSCRContext::gb
GetByteContext gb
Definition: lscrdec.c:50
AVCodecContext::color_range
enum AVColorRange color_range
MPEG vs JPEG YUV range.
Definition: avcodec.h:982
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:274
LSCRContext::cur_h
int cur_h
Definition: lscrdec.c:54
bytestream2_get_bytes_left
static av_always_inline int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:158
error.h
ff_lscr_decoder
const FFCodec ff_lscr_decoder
Definition: lscrdec.c:247
AV_CODEC_ID_LSCR
@ AV_CODEC_ID_LSCR
Definition: codec_id.h:294
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
AVPacket::size
int size
Definition: packet.h:375
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:117
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:353
codec_internal.h
LSCRContext::zstream
FFZStream zstream
Definition: lscrdec.c:57
size
int size
Definition: twinvq_data.h:10344
LSCRContext::row_size
int row_size
Definition: lscrdec.c:53
frame.h
LSCRContext::buffer_size
int buffer_size
Definition: lscrdec.c:44
AVERROR_EXTERNAL
#define AVERROR_EXTERNAL
Generic error in an external library.
Definition: error.h:59
offset
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 offset
Definition: writing_filters.txt:86
ff_png_filter_row
void ff_png_filter_row(PNGDSPContext *dsp, uint8_t *dst, int filter_type, uint8_t *src, uint8_t *last, int size, int bpp)
Definition: pngdec.c:269
ff_pngdsp_init
av_cold void ff_pngdsp_init(PNGDSPContext *dsp)
Definition: pngdsp.c:43
LSCRContext::image_buf
uint8_t * image_buf
Definition: lscrdec.c:51
log.h
packet.h
av_fast_padded_malloc
void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size)
Same behaviour av_fast_malloc but the buffer has additional AV_INPUT_BUFFER_PADDING_SIZE at the end w...
Definition: utils.c:48
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
av_frame_unref
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:487
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:211
ff_inflate_end
void ff_inflate_end(FFZStream *zstream)
Wrapper around inflateEnd().
AVCodecContext::height
int height
Definition: avcodec.h:571
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:608
avcodec.h
ff_reget_buffer
int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Identical in function to ff_get_buffer(), except it reuses the existing buffer if available.
Definition: decode.c:1580
ret
ret
Definition: filter_design.txt:187
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
FF_REGET_BUFFER_FLAG_READONLY
#define FF_REGET_BUFFER_FLAG_READONLY
the returned buffer does not need to be writable
Definition: internal.h:222
decode_frame_lscr
static int decode_frame_lscr(AVCodecContext *avctx, AVFrame *rframe, int *got_frame, AVPacket *avpkt)
Definition: lscrdec.c:110
LSCRContext::crow_buf
uint8_t * crow_buf
Definition: lscrdec.c:45
LSCRContext::crow_size
int crow_size
Definition: lscrdec.c:46
left
Tag MUST be and< 10hcoeff half pel interpolation filter coefficients, hcoeff[0] are the 2 middle coefficients[1] are the next outer ones and so on, resulting in a filter like:...eff[2], hcoeff[1], hcoeff[0], hcoeff[0], hcoeff[1], hcoeff[2] ... the sign of the coefficients is not explicitly stored but alternates after each coeff and coeff[0] is positive, so ...,+,-,+,-,+,+,-,+,-,+,... hcoeff[0] is not explicitly stored but found by subtracting the sum of all stored coefficients with signs from 32 hcoeff[0]=32 - hcoeff[1] - hcoeff[2] - ... a good choice for hcoeff and htaps is htaps=6 hcoeff={40,-10, 2} an alternative which requires more computations at both encoder and decoder side and may or may not be better is htaps=8 hcoeff={42,-14, 6,-2}ref_frames minimum of the number of available reference frames and max_ref_frames for example the first frame after a key frame always has ref_frames=1spatial_decomposition_type wavelet type 0 is a 9/7 symmetric compact integer wavelet 1 is a 5/3 symmetric compact integer wavelet others are reserved stored as delta from last, last is reset to 0 if always_reset||keyframeqlog quality(logarithmic quantizer scale) stored as delta from last, last is reset to 0 if always_reset||keyframemv_scale stored as delta from last, last is reset to 0 if always_reset||keyframe FIXME check that everything works fine if this changes between framesqbias dequantization bias stored as delta from last, last is reset to 0 if always_reset||keyframeblock_max_depth maximum depth of the block tree stored as delta from last, last is reset to 0 if always_reset||keyframequant_table quantization tableHighlevel bitstream structure:==============================--------------------------------------------|Header|--------------------------------------------|------------------------------------|||Block0||||split?||||yes no||||......... intra?||||:Block01 :yes no||||:Block02 :....... ..........||||:Block03 ::y DC ::ref index:||||:Block04 ::cb DC ::motion x :||||......... :cr DC ::motion y :||||....... ..........|||------------------------------------||------------------------------------|||Block1|||...|--------------------------------------------|------------ ------------ ------------|||Y subbands||Cb subbands||Cr subbands||||--- ---||--- ---||--- ---|||||LL0||HL0||||LL0||HL0||||LL0||HL0|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||LH0||HH0||||LH0||HH0||||LH0||HH0|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||HL1||LH1||||HL1||LH1||||HL1||LH1|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||HH1||HL2||||HH1||HL2||||HH1||HL2|||||...||...||...|||------------ ------------ ------------|--------------------------------------------Decoding process:=================------------|||Subbands|------------||||------------|Intra DC||||LL0 subband prediction ------------|\ Dequantization ------------------- \||Reference frames|\ IDWT|------- -------|Motion \|||Frame 0||Frame 1||Compensation . OBMC v -------|------- -------|--------------. \------> Frame n output Frame Frame<----------------------------------/|...|------------------- Range Coder:============Binary Range Coder:------------------- The implemented range coder is an adapted version based upon "Range encoding: an algorithm for removing redundancy from a digitised message." by G. N. N. Martin. The symbols encoded by the Snow range coder are bits(0|1). The associated probabilities are not fix but change depending on the symbol mix seen so far. bit seen|new state ---------+----------------------------------------------- 0|256 - state_transition_table[256 - old_state];1|state_transition_table[old_state];state_transition_table={ 0, 0, 0, 0, 0, 0, 0, 0, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 190, 191, 192, 194, 194, 195, 196, 197, 198, 199, 200, 201, 202, 202, 204, 205, 206, 207, 208, 209, 209, 210, 211, 212, 213, 215, 215, 216, 217, 218, 219, 220, 220, 222, 223, 224, 225, 226, 227, 227, 229, 229, 230, 231, 232, 234, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 248, 0, 0, 0, 0, 0, 0, 0};FIXME Range Coding of integers:------------------------- FIXME Neighboring Blocks:===================left and top are set to the respective blocks unless they are outside of the image in which case they are set to the Null block top-left is set to the top left block unless it is outside of the image in which case it is set to the left block if this block has no larger parent block or it is at the left side of its parent block and the top right block is not outside of the image then the top right block is used for top-right else the top-left block is used Null block y, cb, cr are 128 level, ref, mx and my are 0 Motion Vector Prediction:=========================1. the motion vectors of all the neighboring blocks are scaled to compensate for the difference of reference frames scaled_mv=(mv *(256 *(current_reference+1)/(mv.reference+1))+128)> the median of the scaled left
Definition: snow.txt:386
AVCodecContext
main external API structure.
Definition: avcodec.h:398
lscr_decode_flush
static void lscr_decode_flush(AVCodecContext *avctx)
Definition: lscrdec.c:241
LSCRContext::image_linesize
int image_linesize
Definition: lscrdec.c:52
LSCRContext::buffer
uint8_t * buffer
Definition: lscrdec.c:43
LSCRContext::y
int y
Definition: lscrdec.c:55
AV_PICTURE_TYPE_P
@ AV_PICTURE_TYPE_P
Predicted.
Definition: avutil.h:275
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
FFZStream
Definition: zlib_wrapper.h:27
LSCRContext::avctx
AVCodecContext * avctx
Definition: lscrdec.c:40
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:425
AVPacket
This structure stores compressed data.
Definition: packet.h:351
png.h
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
ff_inflate_init
int ff_inflate_init(FFZStream *zstream, void *logctx)
Wrapper around inflateInit().
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:571
bytestream.h
bytestream2_init
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
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
MKTAG
#define MKTAG(a, b, c, d)
Definition: macros.h:55
h
h
Definition: vp9dsp_template.c:2038
lscr_decode_init
static int lscr_decode_init(AVCodecContext *avctx)
Definition: lscrdec.c:224
decode_idat
static int decode_idat(LSCRContext *s, z_stream *zstream, int length)
Definition: lscrdec.c:76