FFmpeg
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 "decode.h"
47 #include "internal.h"
48 
49 #define TILE_SIZE 8
50 
51 typedef struct Tile {
52  int x, y;
53  int w, h;
54 } Tile;
55 
56 typedef struct RsccContext {
60  unsigned int tiles_size;
62 
64 
65  /* zlib interaction */
67  uLongf inflated_size;
69 } RsccContext;
70 
71 static av_cold int rscc_init(AVCodecContext *avctx)
72 {
73  RsccContext *ctx = avctx->priv_data;
74 
75  /* These needs to be set to estimate uncompressed buffer */
76  int ret = av_image_check_size(avctx->width, avctx->height, 0, avctx);
77  if (ret < 0) {
78  av_log(avctx, AV_LOG_ERROR, "Invalid image size %dx%d.\n",
79  avctx->width, avctx->height);
80  return ret;
81  }
82 
83  /* Allocate reference frame */
84  ctx->reference = av_frame_alloc();
85  if (!ctx->reference)
86  return AVERROR(ENOMEM);
87 
88  /* Get pixel format and the size of the pixel */
89  if (avctx->codec_tag == MKTAG('I', 'S', 'C', 'C')) {
90  if (avctx->extradata && avctx->extradata_size == 4) {
91  if ((avctx->extradata[0] >> 1) & 1) {
92  avctx->pix_fmt = AV_PIX_FMT_BGRA;
93  ctx->component_size = 4;
94  } else {
95  avctx->pix_fmt = AV_PIX_FMT_BGR24;
96  ctx->component_size = 3;
97  }
98  } else {
99  avctx->pix_fmt = AV_PIX_FMT_BGRA;
100  ctx->component_size = 4;
101  }
102  } else if (avctx->codec_tag == MKTAG('R', 'S', 'C', 'C')) {
103  ctx->component_size = avctx->bits_per_coded_sample / 8;
104  switch (avctx->bits_per_coded_sample) {
105  case 8:
106  avctx->pix_fmt = AV_PIX_FMT_PAL8;
107  break;
108  case 16:
109  avctx->pix_fmt = AV_PIX_FMT_RGB555LE;
110  break;
111  case 24:
112  avctx->pix_fmt = AV_PIX_FMT_BGR24;
113  break;
114  case 32:
115  avctx->pix_fmt = AV_PIX_FMT_BGR0;
116  break;
117  default:
118  av_log(avctx, AV_LOG_ERROR, "Invalid bits per pixel value (%d)\n",
119  avctx->bits_per_coded_sample);
120  return AVERROR_INVALIDDATA;
121  }
122  } else {
123  avctx->pix_fmt = AV_PIX_FMT_BGR0;
124  ctx->component_size = 4;
125  av_log(avctx, AV_LOG_WARNING, "Invalid codec tag\n");
126  }
127 
128  /* Store the value to check for keyframes */
129  ctx->inflated_size = avctx->width * avctx->height * ctx->component_size;
130 
131  /* Allocate maximum size possible, a full frame */
132  ctx->inflated_buf = av_malloc(ctx->inflated_size);
133  if (!ctx->inflated_buf)
134  return AVERROR(ENOMEM);
135 
136  return 0;
137 }
138 
140 {
141  RsccContext *ctx = avctx->priv_data;
142 
143  av_freep(&ctx->tiles);
144  av_freep(&ctx->inflated_buf);
145  av_frame_free(&ctx->reference);
146 
147  return 0;
148 }
149 
150 static int rscc_decode_frame(AVCodecContext *avctx, void *data,
151  int *got_frame, AVPacket *avpkt)
152 {
153  RsccContext *ctx = avctx->priv_data;
154  GetByteContext *gbc = &ctx->gbc;
155  GetByteContext tiles_gbc;
156  AVFrame *frame = data;
157  const uint8_t *pixels, *raw;
158  uint8_t *inflated_tiles = NULL;
159  int tiles_nb, packed_size, pixel_size = 0;
160  int i, ret = 0;
161 
162  bytestream2_init(gbc, avpkt->data, avpkt->size);
163 
164  /* Size check */
165  if (bytestream2_get_bytes_left(gbc) < 12) {
166  av_log(avctx, AV_LOG_ERROR, "Packet too small (%d)\n", avpkt->size);
167  return AVERROR_INVALIDDATA;
168  }
169 
170  /* Read number of tiles, and allocate the array */
171  tiles_nb = bytestream2_get_le16(gbc);
172 
173  if (tiles_nb == 0) {
174  av_log(avctx, AV_LOG_DEBUG, "no tiles\n");
175  return avpkt->size;
176  }
177 
178  av_fast_malloc(&ctx->tiles, &ctx->tiles_size,
179  tiles_nb * sizeof(*ctx->tiles));
180  if (!ctx->tiles) {
181  ret = AVERROR(ENOMEM);
182  goto end;
183  }
184 
185  av_log(avctx, AV_LOG_DEBUG, "Frame with %d tiles.\n", tiles_nb);
186 
187  /* When there are more than 5 tiles, they are packed together with
188  * a size header. When that size does not match the number of tiles
189  * times the tile size, it means it needs to be inflated as well */
190  if (tiles_nb > 5) {
191  uLongf packed_tiles_size;
192 
193  if (tiles_nb < 32)
194  packed_tiles_size = bytestream2_get_byte(gbc);
195  else
196  packed_tiles_size = bytestream2_get_le16(gbc);
197 
198  ff_dlog(avctx, "packed tiles of size %lu.\n", packed_tiles_size);
199 
200  /* If necessary, uncompress tiles, and hijack the bytestream reader */
201  if (packed_tiles_size != tiles_nb * TILE_SIZE) {
202  uLongf length = tiles_nb * TILE_SIZE;
203 
204  if (bytestream2_get_bytes_left(gbc) < packed_tiles_size) {
205  ret = AVERROR_INVALIDDATA;
206  goto end;
207  }
208 
209  inflated_tiles = av_malloc(length);
210  if (!inflated_tiles) {
211  ret = AVERROR(ENOMEM);
212  goto end;
213  }
214 
215  ret = uncompress(inflated_tiles, &length,
216  gbc->buffer, packed_tiles_size);
217  if (ret) {
218  av_log(avctx, AV_LOG_ERROR, "Tile deflate error %d.\n", ret);
219  ret = AVERROR_UNKNOWN;
220  goto end;
221  }
222 
223  /* Skip the compressed tile section in the main byte reader,
224  * and point it to read the newly uncompressed data */
225  bytestream2_skip(gbc, packed_tiles_size);
226  bytestream2_init(&tiles_gbc, inflated_tiles, length);
227  gbc = &tiles_gbc;
228  }
229  }
230 
231  /* Fill in array of tiles, keeping track of how many pixels are updated */
232  for (i = 0; i < tiles_nb; i++) {
233  ctx->tiles[i].x = bytestream2_get_le16(gbc);
234  ctx->tiles[i].w = bytestream2_get_le16(gbc);
235  ctx->tiles[i].y = bytestream2_get_le16(gbc);
236  ctx->tiles[i].h = bytestream2_get_le16(gbc);
237 
238  if (pixel_size + ctx->tiles[i].w * (int64_t)ctx->tiles[i].h * ctx->component_size > INT_MAX) {
239  av_log(avctx, AV_LOG_ERROR, "Invalid tile dimensions\n");
240  ret = AVERROR_INVALIDDATA;
241  goto end;
242  }
243 
244  pixel_size += ctx->tiles[i].w * ctx->tiles[i].h * ctx->component_size;
245 
246  ff_dlog(avctx, "tile %d orig(%d,%d) %dx%d.\n", i,
247  ctx->tiles[i].x, ctx->tiles[i].y,
248  ctx->tiles[i].w, ctx->tiles[i].h);
249 
250  if (ctx->tiles[i].w == 0 || ctx->tiles[i].h == 0) {
251  av_log(avctx, AV_LOG_ERROR,
252  "invalid tile %d at (%d.%d) with size %dx%d.\n", i,
253  ctx->tiles[i].x, ctx->tiles[i].y,
254  ctx->tiles[i].w, ctx->tiles[i].h);
255  ret = AVERROR_INVALIDDATA;
256  goto end;
257  } else if (ctx->tiles[i].x + ctx->tiles[i].w > avctx->width ||
258  ctx->tiles[i].y + ctx->tiles[i].h > avctx->height) {
259  av_log(avctx, AV_LOG_ERROR,
260  "out of bounds tile %d at (%d.%d) with size %dx%d.\n", i,
261  ctx->tiles[i].x, ctx->tiles[i].y,
262  ctx->tiles[i].w, ctx->tiles[i].h);
263  ret = AVERROR_INVALIDDATA;
264  goto end;
265  }
266  }
267 
268  /* Reset the reader in case it had been modified before */
269  gbc = &ctx->gbc;
270 
271  /* Extract how much pixel data the tiles contain */
272  if (pixel_size < 0x100)
273  packed_size = bytestream2_get_byte(gbc);
274  else if (pixel_size < 0x10000)
275  packed_size = bytestream2_get_le16(gbc);
276  else if (pixel_size < 0x1000000)
277  packed_size = bytestream2_get_le24(gbc);
278  else
279  packed_size = bytestream2_get_le32(gbc);
280 
281  ff_dlog(avctx, "pixel_size %d packed_size %d.\n", pixel_size, packed_size);
282 
283  if (packed_size < 0) {
284  av_log(avctx, AV_LOG_ERROR, "Invalid tile size %d\n", packed_size);
285  ret = AVERROR_INVALIDDATA;
286  goto end;
287  }
288 
289  /* Get pixels buffer, it may be deflated or just raw */
290  if (pixel_size == packed_size) {
291  if (bytestream2_get_bytes_left(gbc) < pixel_size) {
292  av_log(avctx, AV_LOG_ERROR, "Insufficient input for %d\n", pixel_size);
293  ret = AVERROR_INVALIDDATA;
294  goto end;
295  }
296  pixels = gbc->buffer;
297  } else {
298  uLongf len = ctx->inflated_size;
299  if (bytestream2_get_bytes_left(gbc) < packed_size) {
300  av_log(avctx, AV_LOG_ERROR, "Insufficient input for %d\n", packed_size);
301  ret = AVERROR_INVALIDDATA;
302  goto end;
303  }
304  if (ctx->inflated_size < pixel_size) {
305  ret = AVERROR_INVALIDDATA;
306  goto end;
307  }
308  ret = uncompress(ctx->inflated_buf, &len, gbc->buffer, packed_size);
309  if (ret) {
310  av_log(avctx, AV_LOG_ERROR, "Pixel deflate error %d.\n", ret);
311  ret = AVERROR_UNKNOWN;
312  goto end;
313  }
314  pixels = ctx->inflated_buf;
315  }
316 
317  /* Allocate when needed */
318  ret = ff_reget_buffer(avctx, ctx->reference, 0);
319  if (ret < 0)
320  goto end;
321 
322  /* Pointer to actual pixels, will be updated when data is consumed */
323  raw = pixels;
324  for (i = 0; i < tiles_nb; i++) {
325  uint8_t *dst = ctx->reference->data[0] + ctx->reference->linesize[0] *
326  (avctx->height - ctx->tiles[i].y - 1) +
327  ctx->tiles[i].x * ctx->component_size;
328  av_image_copy_plane(dst, -1 * ctx->reference->linesize[0],
329  raw, ctx->tiles[i].w * ctx->component_size,
330  ctx->tiles[i].w * ctx->component_size,
331  ctx->tiles[i].h);
332  raw += ctx->tiles[i].w * ctx->component_size * ctx->tiles[i].h;
333  }
334 
335  /* Frame is ready to be output */
336  ret = av_frame_ref(frame, ctx->reference);
337  if (ret < 0)
338  goto end;
339 
340  /* Keyframe when the number of pixels updated matches the whole surface */
341  if (pixel_size == ctx->inflated_size) {
342  frame->pict_type = AV_PICTURE_TYPE_I;
343  frame->key_frame = 1;
344  } else {
345  frame->pict_type = AV_PICTURE_TYPE_P;
346  }
347 
348  /* Palette handling */
349  if (avctx->pix_fmt == AV_PIX_FMT_PAL8) {
350  frame->palette_has_changed = ff_copy_palette(ctx->palette, avpkt, avctx);
351  memcpy(frame->data[1], ctx->palette, AVPALETTE_SIZE);
352  }
353  // We only return a picture when enough of it is undamaged, this avoids copying nearly broken frames around
354  if (ctx->valid_pixels < ctx->inflated_size)
355  ctx->valid_pixels += pixel_size;
356  if (ctx->valid_pixels >= ctx->inflated_size * (100 - avctx->discard_damaged_percentage) / 100)
357  *got_frame = 1;
358 
359  ret = avpkt->size;
360 end:
361  av_free(inflated_tiles);
362  return ret;
363 }
364 
366  .name = "rscc",
367  .long_name = NULL_IF_CONFIG_SMALL("innoHeim/Rsupport Screen Capture Codec"),
368  .type = AVMEDIA_TYPE_VIDEO,
369  .id = AV_CODEC_ID_RSCC,
370  .init = rscc_init,
371  .decode = rscc_decode_frame,
372  .close = rscc_close,
373  .priv_data_size = sizeof(RsccContext),
374  .capabilities = AV_CODEC_CAP_DR1,
375  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
377 };
#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:49
uLongf inflated_size
Definition: rscc.c:67
#define NULL
Definition: coverity.c:32
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
This structure describes decoded (raw) audio or video data.
Definition: frame.h:318
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
int ff_copy_palette(void *dst, const AVPacket *src, void *logctx)
Check whether the side-data of src contains a palette of size AVPALETTE_SIZE; if so, copy it to dst and return 1; else return 0.
Definition: decode.c:2095
misc image utilities
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:200
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:370
int component_size
Definition: rscc.c:61
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:746
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
static av_cold int rscc_init(AVCodecContext *avctx)
Definition: rscc.c:71
AVCodec.
Definition: codec.h:197
uint8_t palette[AVPALETTE_SIZE]
Definition: rscc.c:63
unsigned int tiles_size
Definition: rscc.c:60
Tile * tiles
Definition: rscc.c:59
#define TILE_SIZE
Definition: rscc.c:49
#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:41
AVFrame * reference
Definition: rscc.c:58
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:191
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:77
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
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:637
uint8_t * data
Definition: packet.h:369
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:1740
#define av_log(a,...)
static av_always_inline int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:158
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
int valid_pixels
Definition: rscc.c:68
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:168
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:204
uint8_t * inflated_buf
Definition: rscc.c:66
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:117
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:2000
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:215
GLsizei GLsizei * length
Definition: opengl_enc.c:114
const char * name
Name of the codec implementation.
Definition: codec.h:204
static int rscc_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: rscc.c:150
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:57
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:317
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:401
int width
picture width / height.
Definition: avcodec.h:709
Definition: rscc.c:51
AVFormatContext * ctx
Definition: movenc.c:48
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
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:69
int x
Definition: rscc.c:52
int discard_damaged_percentage
The percentage of damaged samples to discard a frame.
Definition: avcodec.h:2328
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:349
main external API structure.
Definition: avcodec.h:536
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:561
int h
Definition: rscc.c:53
int extradata_size
Definition: avcodec.h:638
AVCodec ff_rscc_decoder
Definition: rscc.c:365
static av_cold int rscc_close(AVCodecContext *avctx)
Definition: rscc.c:139
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:475
packed BGR 8:8:8, 32bpp, BGRXBGRX... X=unused/undefined
Definition: pixfmt.h:240
int w
Definition: rscc.c:53
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:332
common internal api header.
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:71
void * priv_data
Definition: avcodec.h:563
#define av_free(p)
int len
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:396
int y
Definition: rscc.c:52
#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:373
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
#define MKTAG(a, b, c, d)
Definition: common.h:478
This structure stores compressed data.
Definition: packet.h:346
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators...
Definition: codec.h:52
int i
Definition: input.c:407
Predicted.
Definition: avutil.h:275