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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;
67 } RsccContext;
68 
69 static av_cold int rscc_init(AVCodecContext *avctx)
70 {
71  RsccContext *ctx = avctx->priv_data;
72 
73  /* These needs to be set to estimate uncompressed buffer */
74  int ret = av_image_check_size(avctx->width, avctx->height, 0, avctx);
75  if (ret < 0) {
76  av_log(avctx, AV_LOG_ERROR, "Invalid image size %dx%d.\n",
77  avctx->width, avctx->height);
78  return ret;
79  }
80 
81  /* Allocate reference frame */
82  ctx->reference = av_frame_alloc();
83  if (!ctx->reference)
84  return AVERROR(ENOMEM);
85 
86  /* Get pixel format and the size of the pixel */
87  if (avctx->codec_tag == MKTAG('I', 'S', 'C', 'C')) {
88  if (avctx->extradata && avctx->extradata_size == 4) {
89  if ((avctx->extradata[0] >> 1) & 1) {
90  avctx->pix_fmt = AV_PIX_FMT_BGRA;
91  ctx->component_size = 4;
92  } else {
93  avctx->pix_fmt = AV_PIX_FMT_BGR24;
94  ctx->component_size = 3;
95  }
96  } else {
97  avctx->pix_fmt = AV_PIX_FMT_BGRA;
98  ctx->component_size = 4;
99  }
100  } else if (avctx->codec_tag == MKTAG('R', 'S', 'C', 'C')) {
101  ctx->component_size = avctx->bits_per_coded_sample / 8;
102  switch (avctx->bits_per_coded_sample) {
103  case 8:
104  avctx->pix_fmt = AV_PIX_FMT_PAL8;
105  break;
106  case 16:
107  avctx->pix_fmt = AV_PIX_FMT_RGB555LE;
108  break;
109  case 24:
110  avctx->pix_fmt = AV_PIX_FMT_BGR24;
111  break;
112  case 32:
113  avctx->pix_fmt = AV_PIX_FMT_BGR0;
114  break;
115  default:
116  av_log(avctx, AV_LOG_ERROR, "Invalid bits per pixel value (%d)\n",
117  avctx->bits_per_coded_sample);
118  return AVERROR_INVALIDDATA;
119  }
120  } else {
121  avctx->pix_fmt = AV_PIX_FMT_BGR0;
122  ctx->component_size = 4;
123  av_log(avctx, AV_LOG_WARNING, "Invalid codec tag\n");
124  }
125 
126  /* Store the value to check for keyframes */
127  ctx->inflated_size = avctx->width * avctx->height * ctx->component_size;
128 
129  /* Allocate maximum size possible, a full frame */
130  ctx->inflated_buf = av_malloc(ctx->inflated_size);
131  if (!ctx->inflated_buf)
132  return AVERROR(ENOMEM);
133 
134  return 0;
135 }
136 
138 {
139  RsccContext *ctx = avctx->priv_data;
140 
141  av_freep(&ctx->tiles);
142  av_freep(&ctx->inflated_buf);
143  av_frame_free(&ctx->reference);
144 
145  return 0;
146 }
147 
148 static int rscc_decode_frame(AVCodecContext *avctx, void *data,
149  int *got_frame, AVPacket *avpkt)
150 {
151  RsccContext *ctx = avctx->priv_data;
152  GetByteContext *gbc = &ctx->gbc;
153  GetByteContext tiles_gbc;
154  AVFrame *frame = data;
155  const uint8_t *pixels, *raw;
156  uint8_t *inflated_tiles = NULL;
157  int tiles_nb, packed_size, pixel_size = 0;
158  int i, ret = 0;
159 
160  bytestream2_init(gbc, avpkt->data, avpkt->size);
161 
162  /* Size check */
163  if (bytestream2_get_bytes_left(gbc) < 12) {
164  av_log(avctx, AV_LOG_ERROR, "Packet too small (%d)\n", avpkt->size);
165  return AVERROR_INVALIDDATA;
166  }
167 
168  /* Read number of tiles, and allocate the array */
169  tiles_nb = bytestream2_get_le16(gbc);
170 
171  if (tiles_nb == 0) {
172  av_log(avctx, AV_LOG_DEBUG, "no tiles\n");
173  return avpkt->size;
174  }
175 
176  av_fast_malloc(&ctx->tiles, &ctx->tiles_size,
177  tiles_nb * sizeof(*ctx->tiles));
178  if (!ctx->tiles) {
179  ret = AVERROR(ENOMEM);
180  goto end;
181  }
182 
183  av_log(avctx, AV_LOG_DEBUG, "Frame with %d tiles.\n", tiles_nb);
184 
185  /* When there are more than 5 tiles, they are packed together with
186  * a size header. When that size does not match the number of tiles
187  * times the tile size, it means it needs to be inflated as well */
188  if (tiles_nb > 5) {
189  uLongf packed_tiles_size;
190 
191  if (tiles_nb < 32)
192  packed_tiles_size = bytestream2_get_byte(gbc);
193  else
194  packed_tiles_size = bytestream2_get_le16(gbc);
195 
196  ff_dlog(avctx, "packed tiles of size %lu.\n", packed_tiles_size);
197 
198  /* If necessary, uncompress tiles, and hijack the bytestream reader */
199  if (packed_tiles_size != tiles_nb * TILE_SIZE) {
200  uLongf length = tiles_nb * TILE_SIZE;
201  inflated_tiles = av_malloc(length);
202  if (!inflated_tiles) {
203  ret = AVERROR(ENOMEM);
204  goto end;
205  }
206 
207  ret = uncompress(inflated_tiles, &length,
208  gbc->buffer, packed_tiles_size);
209  if (ret) {
210  av_log(avctx, AV_LOG_ERROR, "Tile deflate error %d.\n", ret);
211  ret = AVERROR_UNKNOWN;
212  goto end;
213  }
214 
215  /* Skip the compressed tile section in the main byte reader,
216  * and point it to read the newly uncompressed data */
217  bytestream2_skip(gbc, packed_tiles_size);
218  bytestream2_init(&tiles_gbc, inflated_tiles, length);
219  gbc = &tiles_gbc;
220  }
221  }
222 
223  /* Fill in array of tiles, keeping track of how many pixels are updated */
224  for (i = 0; i < tiles_nb; i++) {
225  ctx->tiles[i].x = bytestream2_get_le16(gbc);
226  ctx->tiles[i].w = bytestream2_get_le16(gbc);
227  ctx->tiles[i].y = bytestream2_get_le16(gbc);
228  ctx->tiles[i].h = bytestream2_get_le16(gbc);
229 
230  if (pixel_size + ctx->tiles[i].w * (int64_t)ctx->tiles[i].h * ctx->component_size > INT_MAX) {
231  av_log(avctx, AV_LOG_ERROR, "Invalid tile dimensions\n");
232  ret = AVERROR_INVALIDDATA;
233  goto end;
234  }
235 
236  pixel_size += ctx->tiles[i].w * ctx->tiles[i].h * ctx->component_size;
237 
238  ff_dlog(avctx, "tile %d orig(%d,%d) %dx%d.\n", i,
239  ctx->tiles[i].x, ctx->tiles[i].y,
240  ctx->tiles[i].w, ctx->tiles[i].h);
241 
242  if (ctx->tiles[i].w == 0 || ctx->tiles[i].h == 0) {
243  av_log(avctx, AV_LOG_ERROR,
244  "invalid tile %d at (%d.%d) with size %dx%d.\n", i,
245  ctx->tiles[i].x, ctx->tiles[i].y,
246  ctx->tiles[i].w, ctx->tiles[i].h);
247  ret = AVERROR_INVALIDDATA;
248  goto end;
249  } else if (ctx->tiles[i].x + ctx->tiles[i].w > avctx->width ||
250  ctx->tiles[i].y + ctx->tiles[i].h > avctx->height) {
251  av_log(avctx, AV_LOG_ERROR,
252  "out of bounds 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  }
258  }
259 
260  /* Reset the reader in case it had been modified before */
261  gbc = &ctx->gbc;
262 
263  /* Extract how much pixel data the tiles contain */
264  if (pixel_size < 0x100)
265  packed_size = bytestream2_get_byte(gbc);
266  else if (pixel_size < 0x10000)
267  packed_size = bytestream2_get_le16(gbc);
268  else if (pixel_size < 0x1000000)
269  packed_size = bytestream2_get_le24(gbc);
270  else
271  packed_size = bytestream2_get_le32(gbc);
272 
273  ff_dlog(avctx, "pixel_size %d packed_size %d.\n", pixel_size, packed_size);
274 
275  if (packed_size < 0) {
276  av_log(avctx, AV_LOG_ERROR, "Invalid tile size %d\n", packed_size);
277  ret = AVERROR_INVALIDDATA;
278  goto end;
279  }
280 
281  /* Get pixels buffer, it may be deflated or just raw */
282  if (pixel_size == packed_size) {
283  if (bytestream2_get_bytes_left(gbc) < pixel_size) {
284  av_log(avctx, AV_LOG_ERROR, "Insufficient input for %d\n", pixel_size);
285  ret = AVERROR_INVALIDDATA;
286  goto end;
287  }
288  pixels = gbc->buffer;
289  } else {
290  uLongf len = ctx->inflated_size;
291  if (bytestream2_get_bytes_left(gbc) < packed_size) {
292  av_log(avctx, AV_LOG_ERROR, "Insufficient input for %d\n", packed_size);
293  ret = AVERROR_INVALIDDATA;
294  goto end;
295  }
296  ret = uncompress(ctx->inflated_buf, &len, gbc->buffer, packed_size);
297  if (ret) {
298  av_log(avctx, AV_LOG_ERROR, "Pixel deflate error %d.\n", ret);
299  ret = AVERROR_UNKNOWN;
300  goto end;
301  }
302  pixels = ctx->inflated_buf;
303  }
304 
305  /* Allocate when needed */
306  ret = ff_reget_buffer(avctx, ctx->reference);
307  if (ret < 0)
308  goto end;
309 
310  /* Pointer to actual pixels, will be updated when data is consumed */
311  raw = pixels;
312  for (i = 0; i < tiles_nb; i++) {
313  uint8_t *dst = ctx->reference->data[0] + ctx->reference->linesize[0] *
314  (avctx->height - ctx->tiles[i].y - 1) +
315  ctx->tiles[i].x * ctx->component_size;
316  av_image_copy_plane(dst, -1 * ctx->reference->linesize[0],
317  raw, ctx->tiles[i].w * ctx->component_size,
318  ctx->tiles[i].w * ctx->component_size,
319  ctx->tiles[i].h);
320  raw += ctx->tiles[i].w * ctx->component_size * ctx->tiles[i].h;
321  }
322 
323  /* Frame is ready to be output */
324  ret = av_frame_ref(frame, ctx->reference);
325  if (ret < 0)
326  goto end;
327 
328  /* Keyframe when the number of pixels updated matches the whole surface */
329  if (pixel_size == ctx->inflated_size) {
330  frame->pict_type = AV_PICTURE_TYPE_I;
331  frame->key_frame = 1;
332  } else {
333  frame->pict_type = AV_PICTURE_TYPE_P;
334  }
335 
336  /* Palette handling */
337  if (avctx->pix_fmt == AV_PIX_FMT_PAL8) {
338  int size;
339  const uint8_t *palette = av_packet_get_side_data(avpkt,
341  &size);
342  if (palette && size == AVPALETTE_SIZE) {
343  frame->palette_has_changed = 1;
344  memcpy(ctx->palette, palette, AVPALETTE_SIZE);
345  } else if (palette) {
346  av_log(avctx, AV_LOG_ERROR, "Palette size %d is wrong\n", size);
347  }
348  memcpy (frame->data[1], ctx->palette, AVPALETTE_SIZE);
349  }
350 
351  *got_frame = 1;
352 
353  ret = avpkt->size;
354 end:
355  av_free(inflated_tiles);
356  return ret;
357 }
358 
360  .name = "rscc",
361  .long_name = NULL_IF_CONFIG_SMALL("innoHeim/Rsupport Screen Capture Codec"),
362  .type = AVMEDIA_TYPE_VIDEO,
363  .id = AV_CODEC_ID_RSCC,
364  .init = rscc_init,
365  .decode = rscc_decode_frame,
366  .close = rscc_close,
367  .priv_data_size = sizeof(RsccContext),
368  .capabilities = AV_CODEC_CAP_DR1,
369  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
371 };
#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
This structure describes decoded (raw) audio or video data.
Definition: frame.h:226
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
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: avcodec.h:1446
int component_size
Definition: rscc.c:60
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1743
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:69
AVCodec.
Definition: avcodec.h:3424
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:1965
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:82
#define av_malloc(s)
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:189
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:90
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
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1634
static AVFrame * frame
uint8_t * data
Definition: avcodec.h:1445
const uint8_t * buffer
Definition: bytestream.h:34
#define ff_dlog(a,...)
ptrdiff_t size
Definition: opengl_enc.c:101
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2750
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE bytes worth of palette...
Definition: avcodec.h:1158
#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:350
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
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:186
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
static av_always_inline unsigned int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:154
GLsizei GLsizei * length
Definition: opengl_enc.c:115
const char * name
Name of the codec implementation.
Definition: avcodec.h:3431
static int rscc_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: rscc.c:148
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:488
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:309
int width
picture width / height.
Definition: avcodec.h:1706
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
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:257
main external API structure.
Definition: avcodec.h:1533
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:1558
int h
Definition: rscc.c:52
int extradata_size
Definition: avcodec.h:1635
AVCodec ff_rscc_decoder
Definition: rscc.c:359
static av_cold int rscc_close(AVCodecContext *avctx)
Definition: rscc.c:137
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:383
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:240
common internal api header.
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:71
void * priv_data
Definition: avcodec.h:1560
#define av_free(p)
int pixels
Definition: avisynth_c.h:429
int len
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:304
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:366
This structure stores compressed data.
Definition: avcodec.h:1422
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:968
Predicted.
Definition: avutil.h:275