FFmpeg  4.3.7
rscc.c
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1 /*
2  * innoHeim/Rsupport Screen Capture Codec
3  * Copyright (C) 2015 Vittorio Giovara <vittorio.giovara@gmail.com>
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  * innoHeim/Rsupport Screen Capture Codec decoder
25  *
26  * Fourcc: ISCC, RSCC
27  *
28  * Lossless codec, data stored in tiles, with optional deflate compression.
29  *
30  * Header contains the number of tiles in a frame with the tile coordinates,
31  * and it can be deflated or not. Similarly, pixel data comes after the header
32  * and a variable size value, and it can be deflated or just raw.
33  *
34  * Supports: PAL8, BGRA, BGR24, RGB555
35  */
36 
37 #include <stdint.h>
38 #include <string.h>
39 #include <zlib.h>
40 
41 #include "libavutil/imgutils.h"
42 #include "libavutil/internal.h"
43 
44 #include "avcodec.h"
45 #include "bytestream.h"
46 #include "internal.h"
47 
48 #define TILE_SIZE 8
49 
50 typedef struct Tile {
51  int x, y;
52  int w, h;
53 } Tile;
54 
55 typedef struct RsccContext {
59  unsigned int tiles_size;
61 
63 
64  /* zlib interaction */
66  uLongf inflated_size;
68 } RsccContext;
69 
70 static av_cold int rscc_init(AVCodecContext *avctx)
71 {
72  RsccContext *ctx = avctx->priv_data;
73 
74  /* These needs to be set to estimate uncompressed buffer */
75  int ret = av_image_check_size(avctx->width, avctx->height, 0, avctx);
76  if (ret < 0) {
77  av_log(avctx, AV_LOG_ERROR, "Invalid image size %dx%d.\n",
78  avctx->width, avctx->height);
79  return ret;
80  }
81 
82  /* Allocate reference frame */
83  ctx->reference = av_frame_alloc();
84  if (!ctx->reference)
85  return AVERROR(ENOMEM);
86 
87  /* Get pixel format and the size of the pixel */
88  if (avctx->codec_tag == MKTAG('I', 'S', 'C', 'C')) {
89  if (avctx->extradata && avctx->extradata_size == 4) {
90  if ((avctx->extradata[0] >> 1) & 1) {
91  avctx->pix_fmt = AV_PIX_FMT_BGRA;
92  ctx->component_size = 4;
93  } else {
94  avctx->pix_fmt = AV_PIX_FMT_BGR24;
95  ctx->component_size = 3;
96  }
97  } else {
98  avctx->pix_fmt = AV_PIX_FMT_BGRA;
99  ctx->component_size = 4;
100  }
101  } else if (avctx->codec_tag == MKTAG('R', 'S', 'C', 'C')) {
102  ctx->component_size = avctx->bits_per_coded_sample / 8;
103  switch (avctx->bits_per_coded_sample) {
104  case 8:
105  avctx->pix_fmt = AV_PIX_FMT_PAL8;
106  break;
107  case 16:
108  avctx->pix_fmt = AV_PIX_FMT_RGB555LE;
109  break;
110  case 24:
111  avctx->pix_fmt = AV_PIX_FMT_BGR24;
112  break;
113  case 32:
114  avctx->pix_fmt = AV_PIX_FMT_BGR0;
115  break;
116  default:
117  av_log(avctx, AV_LOG_ERROR, "Invalid bits per pixel value (%d)\n",
118  avctx->bits_per_coded_sample);
119  return AVERROR_INVALIDDATA;
120  }
121  } else {
122  avctx->pix_fmt = AV_PIX_FMT_BGR0;
123  ctx->component_size = 4;
124  av_log(avctx, AV_LOG_WARNING, "Invalid codec tag\n");
125  }
126 
127  /* Store the value to check for keyframes */
128  ctx->inflated_size = avctx->width * avctx->height * ctx->component_size;
129 
130  /* Allocate maximum size possible, a full frame */
131  ctx->inflated_buf = av_malloc(ctx->inflated_size);
132  if (!ctx->inflated_buf)
133  return AVERROR(ENOMEM);
134 
135  return 0;
136 }
137 
139 {
140  RsccContext *ctx = avctx->priv_data;
141 
142  av_freep(&ctx->tiles);
143  av_freep(&ctx->inflated_buf);
144  av_frame_free(&ctx->reference);
145 
146  return 0;
147 }
148 
149 static int rscc_decode_frame(AVCodecContext *avctx, void *data,
150  int *got_frame, AVPacket *avpkt)
151 {
152  RsccContext *ctx = avctx->priv_data;
153  GetByteContext *gbc = &ctx->gbc;
154  GetByteContext tiles_gbc;
155  AVFrame *frame = data;
156  const uint8_t *pixels, *raw;
157  uint8_t *inflated_tiles = NULL;
158  int tiles_nb, packed_size, pixel_size = 0;
159  int i, ret = 0;
160 
161  bytestream2_init(gbc, avpkt->data, avpkt->size);
162 
163  /* Size check */
164  if (bytestream2_get_bytes_left(gbc) < 12) {
165  av_log(avctx, AV_LOG_ERROR, "Packet too small (%d)\n", avpkt->size);
166  return AVERROR_INVALIDDATA;
167  }
168 
169  /* Read number of tiles, and allocate the array */
170  tiles_nb = bytestream2_get_le16(gbc);
171 
172  if (tiles_nb == 0) {
173  av_log(avctx, AV_LOG_DEBUG, "no tiles\n");
174  return avpkt->size;
175  }
176 
177  av_fast_malloc(&ctx->tiles, &ctx->tiles_size,
178  tiles_nb * sizeof(*ctx->tiles));
179  if (!ctx->tiles) {
180  ret = AVERROR(ENOMEM);
181  goto end;
182  }
183 
184  av_log(avctx, AV_LOG_DEBUG, "Frame with %d tiles.\n", tiles_nb);
185 
186  /* When there are more than 5 tiles, they are packed together with
187  * a size header. When that size does not match the number of tiles
188  * times the tile size, it means it needs to be inflated as well */
189  if (tiles_nb > 5) {
190  uLongf packed_tiles_size;
191 
192  if (tiles_nb < 32)
193  packed_tiles_size = bytestream2_get_byte(gbc);
194  else
195  packed_tiles_size = bytestream2_get_le16(gbc);
196 
197  ff_dlog(avctx, "packed tiles of size %lu.\n", packed_tiles_size);
198 
199  /* If necessary, uncompress tiles, and hijack the bytestream reader */
200  if (packed_tiles_size != tiles_nb * TILE_SIZE) {
201  uLongf length = tiles_nb * TILE_SIZE;
202 
203  if (bytestream2_get_bytes_left(gbc) < packed_tiles_size) {
204  ret = AVERROR_INVALIDDATA;
205  goto end;
206  }
207 
208  inflated_tiles = av_malloc(length);
209  if (!inflated_tiles) {
210  ret = AVERROR(ENOMEM);
211  goto end;
212  }
213 
214  ret = uncompress(inflated_tiles, &length,
215  gbc->buffer, packed_tiles_size);
216  if (ret) {
217  av_log(avctx, AV_LOG_ERROR, "Tile deflate error %d.\n", ret);
218  ret = AVERROR_UNKNOWN;
219  goto end;
220  }
221 
222  /* Skip the compressed tile section in the main byte reader,
223  * and point it to read the newly uncompressed data */
224  bytestream2_skip(gbc, packed_tiles_size);
225  bytestream2_init(&tiles_gbc, inflated_tiles, length);
226  gbc = &tiles_gbc;
227  }
228  }
229 
230  /* Fill in array of tiles, keeping track of how many pixels are updated */
231  for (i = 0; i < tiles_nb; i++) {
232  ctx->tiles[i].x = bytestream2_get_le16(gbc);
233  ctx->tiles[i].w = bytestream2_get_le16(gbc);
234  ctx->tiles[i].y = bytestream2_get_le16(gbc);
235  ctx->tiles[i].h = bytestream2_get_le16(gbc);
236 
237  if (pixel_size + ctx->tiles[i].w * (int64_t)ctx->tiles[i].h * ctx->component_size > INT_MAX) {
238  av_log(avctx, AV_LOG_ERROR, "Invalid tile dimensions\n");
239  ret = AVERROR_INVALIDDATA;
240  goto end;
241  }
242 
243  pixel_size += ctx->tiles[i].w * ctx->tiles[i].h * ctx->component_size;
244 
245  ff_dlog(avctx, "tile %d orig(%d,%d) %dx%d.\n", i,
246  ctx->tiles[i].x, ctx->tiles[i].y,
247  ctx->tiles[i].w, ctx->tiles[i].h);
248 
249  if (ctx->tiles[i].w == 0 || ctx->tiles[i].h == 0) {
250  av_log(avctx, AV_LOG_ERROR,
251  "invalid tile %d at (%d.%d) with size %dx%d.\n", i,
252  ctx->tiles[i].x, ctx->tiles[i].y,
253  ctx->tiles[i].w, ctx->tiles[i].h);
254  ret = AVERROR_INVALIDDATA;
255  goto end;
256  } else if (ctx->tiles[i].x + ctx->tiles[i].w > avctx->width ||
257  ctx->tiles[i].y + ctx->tiles[i].h > avctx->height) {
258  av_log(avctx, AV_LOG_ERROR,
259  "out of bounds tile %d at (%d.%d) with size %dx%d.\n", i,
260  ctx->tiles[i].x, ctx->tiles[i].y,
261  ctx->tiles[i].w, ctx->tiles[i].h);
262  ret = AVERROR_INVALIDDATA;
263  goto end;
264  }
265  }
266 
267  /* Reset the reader in case it had been modified before */
268  gbc = &ctx->gbc;
269 
270  /* Extract how much pixel data the tiles contain */
271  if (pixel_size < 0x100)
272  packed_size = bytestream2_get_byte(gbc);
273  else if (pixel_size < 0x10000)
274  packed_size = bytestream2_get_le16(gbc);
275  else if (pixel_size < 0x1000000)
276  packed_size = bytestream2_get_le24(gbc);
277  else
278  packed_size = bytestream2_get_le32(gbc);
279 
280  ff_dlog(avctx, "pixel_size %d packed_size %d.\n", pixel_size, packed_size);
281 
282  if (packed_size < 0) {
283  av_log(avctx, AV_LOG_ERROR, "Invalid tile size %d\n", packed_size);
284  ret = AVERROR_INVALIDDATA;
285  goto end;
286  }
287 
288  /* Get pixels buffer, it may be deflated or just raw */
289  if (pixel_size == packed_size) {
290  if (bytestream2_get_bytes_left(gbc) < pixel_size) {
291  av_log(avctx, AV_LOG_ERROR, "Insufficient input for %d\n", pixel_size);
292  ret = AVERROR_INVALIDDATA;
293  goto end;
294  }
295  pixels = gbc->buffer;
296  } else {
297  uLongf len = ctx->inflated_size;
298  if (bytestream2_get_bytes_left(gbc) < packed_size) {
299  av_log(avctx, AV_LOG_ERROR, "Insufficient input for %d\n", packed_size);
300  ret = AVERROR_INVALIDDATA;
301  goto end;
302  }
303  if (ctx->inflated_size < pixel_size) {
304  ret = AVERROR_INVALIDDATA;
305  goto end;
306  }
307  ret = uncompress(ctx->inflated_buf, &len, gbc->buffer, packed_size);
308  if (ret) {
309  av_log(avctx, AV_LOG_ERROR, "Pixel deflate error %d.\n", ret);
310  ret = AVERROR_UNKNOWN;
311  goto end;
312  }
313  pixels = ctx->inflated_buf;
314  }
315 
316  /* Allocate when needed */
317  ret = ff_reget_buffer(avctx, ctx->reference, 0);
318  if (ret < 0)
319  goto end;
320 
321  /* Pointer to actual pixels, will be updated when data is consumed */
322  raw = pixels;
323  for (i = 0; i < tiles_nb; i++) {
324  uint8_t *dst = ctx->reference->data[0] + ctx->reference->linesize[0] *
325  (avctx->height - ctx->tiles[i].y - 1) +
326  ctx->tiles[i].x * ctx->component_size;
327  av_image_copy_plane(dst, -1 * ctx->reference->linesize[0],
328  raw, ctx->tiles[i].w * ctx->component_size,
329  ctx->tiles[i].w * ctx->component_size,
330  ctx->tiles[i].h);
331  raw += ctx->tiles[i].w * ctx->component_size * ctx->tiles[i].h;
332  }
333 
334  /* Frame is ready to be output */
335  ret = av_frame_ref(frame, ctx->reference);
336  if (ret < 0)
337  goto end;
338 
339  /* Keyframe when the number of pixels updated matches the whole surface */
340  if (pixel_size == ctx->inflated_size) {
341  frame->pict_type = AV_PICTURE_TYPE_I;
342  frame->key_frame = 1;
343  } else {
344  frame->pict_type = AV_PICTURE_TYPE_P;
345  }
346 
347  /* Palette handling */
348  if (avctx->pix_fmt == AV_PIX_FMT_PAL8) {
349  int size;
350  const uint8_t *palette = av_packet_get_side_data(avpkt,
352  &size);
353  if (palette && size == AVPALETTE_SIZE) {
354  frame->palette_has_changed = 1;
355  memcpy(ctx->palette, palette, AVPALETTE_SIZE);
356  } else if (palette) {
357  av_log(avctx, AV_LOG_ERROR, "Palette size %d is wrong\n", size);
358  }
359  memcpy (frame->data[1], ctx->palette, AVPALETTE_SIZE);
360  }
361  // We only return a picture when enough of it is undamaged, this avoids copying nearly broken frames around
362  if (ctx->valid_pixels < ctx->inflated_size)
363  ctx->valid_pixels += pixel_size;
364  if (ctx->valid_pixels >= ctx->inflated_size * (100 - avctx->discard_damaged_percentage) / 100)
365  *got_frame = 1;
366 
367  ret = avpkt->size;
368 end:
369  av_free(inflated_tiles);
370  return ret;
371 }
372 
374  .name = "rscc",
375  .long_name = NULL_IF_CONFIG_SMALL("innoHeim/Rsupport Screen Capture Codec"),
376  .type = AVMEDIA_TYPE_VIDEO,
377  .id = AV_CODEC_ID_RSCC,
378  .init = rscc_init,
379  .decode = rscc_decode_frame,
380  .close = rscc_close,
381  .priv_data_size = sizeof(RsccContext),
382  .capabilities = AV_CODEC_CAP_DR1,
383  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
385 };
#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
uLongf inflated_size
Definition: rscc.c:66
#define NULL
Definition: coverity.c:32
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int size
This structure describes decoded (raw) audio or video data.
Definition: frame.h:300
misc image utilities
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
packed RGB 5:5:5, 16bpp, (msb)1X 5R 5G 5B(lsb), little-endian, X=unused/undefined ...
Definition: pixfmt.h:108
int size
Definition: packet.h:356
int component_size
Definition: rscc.c:60
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:736
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:133
static av_cold int rscc_init(AVCodecContext *avctx)
Definition: rscc.c:70
AVCodec.
Definition: codec.h:190
uint8_t palette[AVPALETTE_SIZE]
Definition: rscc.c:62
unsigned int tiles_size
Definition: rscc.c:59
Tile * tiles
Definition: rscc.c:58
#define TILE_SIZE
Definition: rscc.c:48
#define FF_CODEC_CAP_INIT_THREADSAFE
The codec does not modify any global variables in the init function, allowing to call the init functi...
Definition: internal.h:40
AVFrame * reference
Definition: rscc.c:57
uint8_t
#define av_cold
Definition: attributes.h:88
#define av_malloc(s)
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:190
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:77
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:92
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:444
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:627
static AVFrame * frame
const char data[16]
Definition: mxf.c:91
uint8_t * data
Definition: packet.h:355
const uint8_t * buffer
Definition: bytestream.h:34
#define ff_dlog(a,...)
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1750
#define av_log(a,...)
static av_always_inline int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:154
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
int valid_pixels
Definition: rscc.c:67
An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE bytes worth of palette...
Definition: packet.h:46
#define AVERROR(e)
Definition: error.h:43
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:164
uint8_t * av_packet_get_side_data(const AVPacket *pkt, enum AVPacketSideDataType type, int *size)
Get side information from packet.
Definition: avpacket.c:353
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:203
uint8_t * inflated_buf
Definition: rscc.c:65
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:188
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:1961
packed BGRA 8:8:8:8, 32bpp, BGRABGRA...
Definition: pixfmt.h:95
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
const char * name
Name of the codec implementation.
Definition: codec.h:197
static int rscc_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: rscc.c:149
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:502
GetByteContext gbc
Definition: rscc.c:56
common internal API header
int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
Check if the given dimension of an image is valid, meaning that all bytes of the image can be address...
Definition: imgutils.c:282
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:383
int width
picture width / height.
Definition: avcodec.h:699
Definition: rscc.c:50
AVFormatContext * ctx
Definition: movenc.c:48
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:69
int x
Definition: rscc.c:51
int discard_damaged_percentage
The percentage of damaged samples to discard a frame.
Definition: avcodec.h:2336
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:331
main external API structure.
Definition: avcodec.h:526
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> (&#39;D&#39;<<24) + (&#39;C&#39;<<16) + (&#39;B&#39;<<8) + &#39;A&#39;).
Definition: avcodec.h:551
int h
Definition: rscc.c:52
int extradata_size
Definition: avcodec.h:628
AVCodec ff_rscc_decoder
Definition: rscc.c:373
static av_cold int rscc_close(AVCodecContext *avctx)
Definition: rscc.c:138
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:457
packed BGR 8:8:8, 32bpp, BGRXBGRX... X=unused/undefined
Definition: pixfmt.h:240
int w
Definition: rscc.c:52
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:314
common internal api header.
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:71
void * priv_data
Definition: avcodec.h:553
#define av_free(p)
int len
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:378
int y
Definition: rscc.c:51
#define av_freep(p)
void av_image_copy_plane(uint8_t *dst, int dst_linesize, const uint8_t *src, int src_linesize, int bytewidth, int height)
Copy image plane from src to dst.
Definition: imgutils.c:338
#define MKTAG(a, b, c, d)
Definition: common.h:406
This structure stores compressed data.
Definition: packet.h:332
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:50
Predicted.
Definition: avutil.h:275