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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  avctx->pix_fmt = AV_PIX_FMT_BGRA;
89  ctx->component_size = 4;
90  } else if (avctx->codec_tag == MKTAG('R', 'S', 'C', 'C')) {
91  ctx->component_size = avctx->bits_per_coded_sample / 8;
92  switch (avctx->bits_per_coded_sample) {
93  case 8:
94  avctx->pix_fmt = AV_PIX_FMT_PAL8;
95  break;
96  case 16:
98  break;
99  case 24:
100  avctx->pix_fmt = AV_PIX_FMT_BGR24;
101  break;
102  case 32:
103  avctx->pix_fmt = AV_PIX_FMT_BGR0;
104  break;
105  default:
106  av_log(avctx, AV_LOG_ERROR, "Invalid bits per pixel value (%d)\n",
107  avctx->bits_per_coded_sample);
108  return AVERROR_INVALIDDATA;
109  }
110  } else {
111  avctx->pix_fmt = AV_PIX_FMT_BGR0;
112  ctx->component_size = 4;
113  av_log(avctx, AV_LOG_WARNING, "Invalid codec tag\n");
114  }
115 
116  /* Store the value to check for keyframes */
117  ctx->inflated_size = avctx->width * avctx->height * ctx->component_size;
118 
119  /* Allocate maximum size possible, a full frame */
120  ctx->inflated_buf = av_malloc(ctx->inflated_size);
121  if (!ctx->inflated_buf)
122  return AVERROR(ENOMEM);
123 
124  return 0;
125 }
126 
128 {
129  RsccContext *ctx = avctx->priv_data;
130 
131  av_freep(&ctx->tiles);
132  av_freep(&ctx->inflated_buf);
133  av_frame_free(&ctx->reference);
134 
135  return 0;
136 }
137 
138 static int rscc_decode_frame(AVCodecContext *avctx, void *data,
139  int *got_frame, AVPacket *avpkt)
140 {
141  RsccContext *ctx = avctx->priv_data;
142  GetByteContext *gbc = &ctx->gbc;
143  GetByteContext tiles_gbc;
144  AVFrame *frame = data;
145  const uint8_t *pixels, *raw;
146  uint8_t *inflated_tiles = NULL;
147  int tiles_nb, packed_size, pixel_size = 0;
148  int i, ret = 0;
149 
150  bytestream2_init(gbc, avpkt->data, avpkt->size);
151 
152  /* Size check */
153  if (bytestream2_get_bytes_left(gbc) < 12) {
154  av_log(avctx, AV_LOG_ERROR, "Packet too small (%d)\n", avpkt->size);
155  return AVERROR_INVALIDDATA;
156  }
157 
158  /* Read number of tiles, and allocate the array */
159  tiles_nb = bytestream2_get_le16(gbc);
160 
161  if (tiles_nb == 0) {
162  av_log(avctx, AV_LOG_DEBUG, "no tiles\n");
163  return avpkt->size;
164  }
165 
166  av_fast_malloc(&ctx->tiles, &ctx->tiles_size,
167  tiles_nb * sizeof(*ctx->tiles));
168  if (!ctx->tiles) {
169  ret = AVERROR(ENOMEM);
170  goto end;
171  }
172 
173  av_log(avctx, AV_LOG_DEBUG, "Frame with %d tiles.\n", tiles_nb);
174 
175  /* When there are more than 5 tiles, they are packed together with
176  * a size header. When that size does not match the number of tiles
177  * times the tile size, it means it needs to be inflated as well */
178  if (tiles_nb > 5) {
179  uLongf packed_tiles_size;
180 
181  if (tiles_nb < 32)
182  packed_tiles_size = bytestream2_get_byte(gbc);
183  else
184  packed_tiles_size = bytestream2_get_le16(gbc);
185 
186  ff_dlog(avctx, "packed tiles of size %lu.\n", packed_tiles_size);
187 
188  /* If necessary, uncompress tiles, and hijack the bytestream reader */
189  if (packed_tiles_size != tiles_nb * TILE_SIZE) {
190  uLongf length = tiles_nb * TILE_SIZE;
191  inflated_tiles = av_malloc(length);
192  if (!inflated_tiles) {
193  ret = AVERROR(ENOMEM);
194  goto end;
195  }
196 
197  ret = uncompress(inflated_tiles, &length,
198  gbc->buffer, packed_tiles_size);
199  if (ret) {
200  av_log(avctx, AV_LOG_ERROR, "Tile deflate error %d.\n", ret);
201  ret = AVERROR_UNKNOWN;
202  goto end;
203  }
204 
205  /* Skip the compressed tile section in the main byte reader,
206  * and point it to read the newly uncompressed data */
207  bytestream2_skip(gbc, packed_tiles_size);
208  bytestream2_init(&tiles_gbc, inflated_tiles, length);
209  gbc = &tiles_gbc;
210  }
211  }
212 
213  /* Fill in array of tiles, keeping track of how many pixels are updated */
214  for (i = 0; i < tiles_nb; i++) {
215  ctx->tiles[i].x = bytestream2_get_le16(gbc);
216  ctx->tiles[i].w = bytestream2_get_le16(gbc);
217  ctx->tiles[i].y = bytestream2_get_le16(gbc);
218  ctx->tiles[i].h = bytestream2_get_le16(gbc);
219 
220  if (pixel_size + ctx->tiles[i].w * (int64_t)ctx->tiles[i].h * ctx->component_size > INT_MAX) {
221  av_log(avctx, AV_LOG_ERROR, "Invalid tile dimensions\n");
222  ret = AVERROR_INVALIDDATA;
223  goto end;
224  }
225 
226  pixel_size += ctx->tiles[i].w * ctx->tiles[i].h * ctx->component_size;
227 
228  ff_dlog(avctx, "tile %d orig(%d,%d) %dx%d.\n", i,
229  ctx->tiles[i].x, ctx->tiles[i].y,
230  ctx->tiles[i].w, ctx->tiles[i].h);
231 
232  if (ctx->tiles[i].w == 0 || ctx->tiles[i].h == 0) {
233  av_log(avctx, AV_LOG_ERROR,
234  "invalid tile %d at (%d.%d) with size %dx%d.\n", i,
235  ctx->tiles[i].x, ctx->tiles[i].y,
236  ctx->tiles[i].w, ctx->tiles[i].h);
237  ret = AVERROR_INVALIDDATA;
238  goto end;
239  } else if (ctx->tiles[i].x + ctx->tiles[i].w > avctx->width ||
240  ctx->tiles[i].y + ctx->tiles[i].h > avctx->height) {
241  av_log(avctx, AV_LOG_ERROR,
242  "out of bounds tile %d at (%d.%d) with size %dx%d.\n", i,
243  ctx->tiles[i].x, ctx->tiles[i].y,
244  ctx->tiles[i].w, ctx->tiles[i].h);
245  ret = AVERROR_INVALIDDATA;
246  goto end;
247  }
248  }
249 
250  /* Reset the reader in case it had been modified before */
251  gbc = &ctx->gbc;
252 
253  /* Extract how much pixel data the tiles contain */
254  if (pixel_size < 0x100)
255  packed_size = bytestream2_get_byte(gbc);
256  else if (pixel_size < 0x10000)
257  packed_size = bytestream2_get_le16(gbc);
258  else if (pixel_size < 0x1000000)
259  packed_size = bytestream2_get_le24(gbc);
260  else
261  packed_size = bytestream2_get_le32(gbc);
262 
263  ff_dlog(avctx, "pixel_size %d packed_size %d.\n", pixel_size, packed_size);
264 
265  if (packed_size < 0) {
266  av_log(avctx, AV_LOG_ERROR, "Invalid tile size %d\n", packed_size);
267  ret = AVERROR_INVALIDDATA;
268  goto end;
269  }
270 
271  /* Get pixels buffer, it may be deflated or just raw */
272  if (pixel_size == packed_size) {
273  if (bytestream2_get_bytes_left(gbc) < pixel_size) {
274  av_log(avctx, AV_LOG_ERROR, "Insufficient input for %d\n", pixel_size);
275  ret = AVERROR_INVALIDDATA;
276  goto end;
277  }
278  pixels = gbc->buffer;
279  } else {
280  uLongf len = ctx->inflated_size;
281  if (bytestream2_get_bytes_left(gbc) < packed_size) {
282  av_log(avctx, AV_LOG_ERROR, "Insufficient input for %d\n", packed_size);
283  ret = AVERROR_INVALIDDATA;
284  goto end;
285  }
286  ret = uncompress(ctx->inflated_buf, &len, gbc->buffer, packed_size);
287  if (ret) {
288  av_log(avctx, AV_LOG_ERROR, "Pixel deflate error %d.\n", ret);
289  ret = AVERROR_UNKNOWN;
290  goto end;
291  }
292  pixels = ctx->inflated_buf;
293  }
294 
295  /* Allocate when needed */
296  ret = ff_reget_buffer(avctx, ctx->reference);
297  if (ret < 0)
298  goto end;
299 
300  /* Pointer to actual pixels, will be updated when data is consumed */
301  raw = pixels;
302  for (i = 0; i < tiles_nb; i++) {
303  uint8_t *dst = ctx->reference->data[0] + ctx->reference->linesize[0] *
304  (avctx->height - ctx->tiles[i].y - 1) +
305  ctx->tiles[i].x * ctx->component_size;
306  av_image_copy_plane(dst, -1 * ctx->reference->linesize[0],
307  raw, ctx->tiles[i].w * ctx->component_size,
308  ctx->tiles[i].w * ctx->component_size,
309  ctx->tiles[i].h);
310  raw += ctx->tiles[i].w * ctx->component_size * ctx->tiles[i].h;
311  }
312 
313  /* Frame is ready to be output */
314  ret = av_frame_ref(frame, ctx->reference);
315  if (ret < 0)
316  goto end;
317 
318  /* Keyframe when the number of pixels updated matches the whole surface */
319  if (pixel_size == ctx->inflated_size) {
320  frame->pict_type = AV_PICTURE_TYPE_I;
321  frame->key_frame = 1;
322  } else {
323  frame->pict_type = AV_PICTURE_TYPE_P;
324  }
325 
326  /* Palette handling */
327  if (avctx->pix_fmt == AV_PIX_FMT_PAL8) {
328  int size;
329  const uint8_t *palette = av_packet_get_side_data(avpkt,
331  &size);
332  if (palette && size == AVPALETTE_SIZE) {
333  frame->palette_has_changed = 1;
334  memcpy(ctx->palette, palette, AVPALETTE_SIZE);
335  } else if (palette) {
336  av_log(avctx, AV_LOG_ERROR, "Palette size %d is wrong\n", size);
337  }
338  memcpy (frame->data[1], ctx->palette, AVPALETTE_SIZE);
339  }
340 
341  *got_frame = 1;
342 
343  ret = avpkt->size;
344 end:
345  av_free(inflated_tiles);
346  return ret;
347 }
348 
350  .name = "rscc",
351  .long_name = NULL_IF_CONFIG_SMALL("innoHeim/Rsupport Screen Capture Codec"),
352  .type = AVMEDIA_TYPE_VIDEO,
353  .id = AV_CODEC_ID_RSCC,
354  .init = rscc_init,
355  .decode = rscc_decode_frame,
356  .close = rscc_close,
357  .priv_data_size = sizeof(RsccContext),
358  .capabilities = AV_CODEC_CAP_DR1,
359  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
361 };
#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:218
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:1434
int component_size
Definition: rscc.c:60
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1730
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:3411
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:1969
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:441
static AVFrame * frame
uint8_t * data
Definition: avcodec.h:1433
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:2737
#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:1152
#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:3418
static int rscc_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: rscc.c:138
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:301
int width
picture width / height.
Definition: avcodec.h:1693
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:249
main external API structure.
Definition: avcodec.h:1521
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:1546
int h
Definition: rscc.c:52
AVCodec ff_rscc_decoder
Definition: rscc.c:349
static av_cold int rscc_close(AVCodecContext *avctx)
Definition: rscc.c:127
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:375
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:232
common internal api header.
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:71
void * priv_data
Definition: avcodec.h:1548
#define av_free(p)
int pixels
Definition: avisynth_c.h:429
int len
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:296
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:1410
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:962
Predicted.
Definition: avutil.h:275