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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: BGRA, BGR24, RGB555, PAL8
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  uint32_t pal[AVPALETTE_COUNT];
62 
63  /* zlib interaction */
65  uLongf inflated_size;
66 } RsccContext;
67 
68 static av_cold int rscc_init(AVCodecContext *avctx)
69 {
70  RsccContext *ctx = avctx->priv_data;
71 
72  /* These needs to be set to estimate uncompressed buffer */
73  int ret = av_image_check_size(avctx->width, avctx->height, 0, avctx);
74  if (ret < 0) {
75  av_log(avctx, AV_LOG_ERROR, "Invalid image size %dx%d.\n",
76  avctx->width, avctx->height);
77  return ret;
78  }
79 
80  /* Allocate reference frame */
81  ctx->reference = av_frame_alloc();
82  if (!ctx->reference)
83  return AVERROR(ENOMEM);
84 
85  /* Get pixel format and the size of the pixel */
86  if (avctx->codec_tag == MKTAG('I', 'S', 'C', 'C')) {
87  avctx->pix_fmt = AV_PIX_FMT_BGRA;
88  ctx->component_size = 4;
89  } else if (avctx->codec_tag == MKTAG('R', 'S', 'C', 'C')) {
90  ctx->component_size = avctx->bits_per_coded_sample / 8;
91  switch (avctx->bits_per_coded_sample) {
92  case 8:
93  avctx->pix_fmt = AV_PIX_FMT_PAL8;
94  break;
95  case 16:
97  break;
98  case 24:
99  avctx->pix_fmt = AV_PIX_FMT_BGR24;
100  break;
101  case 32:
102  avctx->pix_fmt = AV_PIX_FMT_BGR0;
103  break;
104  default:
105  av_log(avctx, AV_LOG_ERROR, "Invalid bits per pixel value (%d)\n",
106  avctx->bits_per_coded_sample);
107  return AVERROR_INVALIDDATA;
108  }
109  } else {
110  avctx->pix_fmt = AV_PIX_FMT_BGR0;
111  ctx->component_size = 4;
112  av_log(avctx, AV_LOG_WARNING, "Invalid codec tag\n");
113  }
114 
115  /* Store the value to check for keyframes */
116  ctx->inflated_size = avctx->width * avctx->height * ctx->component_size;
117 
118  /* Allocate maximum size possible, a full frame */
119  ctx->inflated_buf = av_malloc(ctx->inflated_size);
120  if (!ctx->inflated_buf)
121  return AVERROR(ENOMEM);
122 
123  return 0;
124 }
125 
127 {
128  RsccContext *ctx = avctx->priv_data;
129 
130  av_freep(&ctx->tiles);
131  av_freep(&ctx->inflated_buf);
132  av_frame_free(&ctx->reference);
133 
134  return 0;
135 }
136 
137 static int rscc_decode_frame(AVCodecContext *avctx, void *data,
138  int *got_frame, AVPacket *avpkt)
139 {
140  RsccContext *ctx = avctx->priv_data;
141  GetByteContext *gbc = &ctx->gbc;
142  GetByteContext tiles_gbc;
143  AVFrame *frame = data;
144  const uint8_t *pixels, *raw;
145  uint8_t *inflated_tiles = NULL;
146  int tiles_nb, packed_size, pixel_size = 0;
147  int i, ret = 0;
148 
149  bytestream2_init(gbc, avpkt->data, avpkt->size);
150 
151  /* Size check */
152  if (bytestream2_get_bytes_left(gbc) < 12) {
153  av_log(avctx, AV_LOG_ERROR, "Packet too small (%d)\n", avpkt->size);
154  return AVERROR_INVALIDDATA;
155  }
156 
157  /* Read number of tiles, and allocate the array */
158  tiles_nb = bytestream2_get_le16(gbc);
159  av_fast_malloc(&ctx->tiles, &ctx->tiles_size,
160  tiles_nb * sizeof(*ctx->tiles));
161  if (!ctx->tiles) {
162  ret = AVERROR(ENOMEM);
163  goto end;
164  }
165 
166  av_log(avctx, AV_LOG_DEBUG, "Frame with %d tiles.\n", tiles_nb);
167 
168  /* When there are more than 5 tiles, they are packed together with
169  * a size header. When that size does not match the number of tiles
170  * times the tile size, it means it needs to be inflated as well */
171  if (tiles_nb > 5) {
172  uLongf packed_tiles_size;
173 
174  if (tiles_nb < 32)
175  packed_tiles_size = bytestream2_get_byte(gbc);
176  else
177  packed_tiles_size = bytestream2_get_le16(gbc);
178 
179  ff_dlog(avctx, "packed tiles of size %lu.\n", packed_tiles_size);
180 
181  /* If necessary, uncompress tiles, and hijack the bytestream reader */
182  if (packed_tiles_size != tiles_nb * TILE_SIZE) {
183  uLongf length = tiles_nb * TILE_SIZE;
184  inflated_tiles = av_malloc(length);
185  if (!inflated_tiles) {
186  ret = AVERROR(ENOMEM);
187  goto end;
188  }
189 
190  ret = uncompress(inflated_tiles, &length,
191  gbc->buffer, packed_tiles_size);
192  if (ret) {
193  av_log(avctx, AV_LOG_ERROR, "Tile deflate error %d.\n", ret);
194  ret = AVERROR_UNKNOWN;
195  goto end;
196  }
197 
198  /* Skip the compressed tile section in the main byte reader,
199  * and point it to read the newly uncompressed data */
200  bytestream2_skip(gbc, packed_tiles_size);
201  bytestream2_init(&tiles_gbc, inflated_tiles, length);
202  gbc = &tiles_gbc;
203  }
204  }
205 
206  /* Fill in array of tiles, keeping track of how many pixels are updated */
207  for (i = 0; i < tiles_nb; i++) {
208  ctx->tiles[i].x = bytestream2_get_le16(gbc);
209  ctx->tiles[i].w = bytestream2_get_le16(gbc);
210  ctx->tiles[i].y = bytestream2_get_le16(gbc);
211  ctx->tiles[i].h = bytestream2_get_le16(gbc);
212 
213  pixel_size += ctx->tiles[i].w * ctx->tiles[i].h * ctx->component_size;
214 
215  ff_dlog(avctx, "tile %d orig(%d,%d) %dx%d.\n", i,
216  ctx->tiles[i].x, ctx->tiles[i].y,
217  ctx->tiles[i].w, ctx->tiles[i].h);
218 
219  if (ctx->tiles[i].w == 0 || ctx->tiles[i].h == 0) {
220  av_log(avctx, AV_LOG_ERROR,
221  "invalid tile %d at (%d.%d) with size %dx%d.\n", i,
222  ctx->tiles[i].x, ctx->tiles[i].y,
223  ctx->tiles[i].w, ctx->tiles[i].h);
224  ret = AVERROR_INVALIDDATA;
225  goto end;
226  } else if (ctx->tiles[i].x + ctx->tiles[i].w > avctx->width ||
227  ctx->tiles[i].y + ctx->tiles[i].h > avctx->height) {
228  av_log(avctx, AV_LOG_ERROR,
229  "out of bounds tile %d at (%d.%d) with size %dx%d.\n", i,
230  ctx->tiles[i].x, ctx->tiles[i].y,
231  ctx->tiles[i].w, ctx->tiles[i].h);
232  ret = AVERROR_INVALIDDATA;
233  goto end;
234  }
235  }
236 
237  /* Reset the reader in case it had been modified before */
238  gbc = &ctx->gbc;
239 
240  /* Extract how much pixel data the tiles contain */
241  if (pixel_size < 0x100)
242  packed_size = bytestream2_get_byte(gbc);
243  else if (pixel_size < 0x10000)
244  packed_size = bytestream2_get_le16(gbc);
245  else if (pixel_size < 0x1000000)
246  packed_size = bytestream2_get_le24(gbc);
247  else
248  packed_size = bytestream2_get_le32(gbc);
249 
250  ff_dlog(avctx, "pixel_size %d packed_size %d.\n", pixel_size, packed_size);
251 
252  if (packed_size < 0) {
253  av_log(avctx, AV_LOG_ERROR, "Invalid tile size %d\n", packed_size);
254  ret = AVERROR_INVALIDDATA;
255  goto end;
256  }
257 
258  /* Get pixels buffer, it may be deflated or just raw */
259  if (pixel_size == packed_size) {
260  if (bytestream2_get_bytes_left(gbc) < pixel_size) {
261  av_log(avctx, AV_LOG_ERROR, "Insufficient input for %d\n", pixel_size);
262  ret = AVERROR_INVALIDDATA;
263  goto end;
264  }
265  pixels = gbc->buffer;
266  } else {
267  uLongf len = ctx->inflated_size;
268  if (bytestream2_get_bytes_left(gbc) < packed_size) {
269  av_log(avctx, AV_LOG_ERROR, "Insufficient input for %d\n", packed_size);
270  ret = AVERROR_INVALIDDATA;
271  goto end;
272  }
273  ret = uncompress(ctx->inflated_buf, &len, gbc->buffer, packed_size);
274  if (ret) {
275  av_log(avctx, AV_LOG_ERROR, "Pixel deflate error %d.\n", ret);
276  ret = AVERROR_UNKNOWN;
277  goto end;
278  }
279  pixels = ctx->inflated_buf;
280  }
281 
282  /* Allocate when needed */
283  ret = ff_reget_buffer(avctx, ctx->reference);
284  if (ret < 0)
285  goto end;
286 
287  /* Pointer to actual pixels, will be updated when data is consumed */
288  raw = pixels;
289  for (i = 0; i < tiles_nb; i++) {
290  uint8_t *dst = ctx->reference->data[0] + ctx->reference->linesize[0] *
291  (avctx->height - ctx->tiles[i].y - 1) +
292  ctx->tiles[i].x * ctx->component_size;
293  av_image_copy_plane(dst, -1 * ctx->reference->linesize[0],
294  raw, ctx->tiles[i].w * ctx->component_size,
295  ctx->tiles[i].w * ctx->component_size,
296  ctx->tiles[i].h);
297  raw += ctx->tiles[i].w * ctx->component_size * ctx->tiles[i].h;
298  }
299 
300  /* Frame is ready to be output */
301  ret = av_frame_ref(frame, ctx->reference);
302  if (ret < 0)
303  goto end;
304 
305  /* Keyframe when the number of pixels updated matches the whole surface */
306  if (pixel_size == ctx->inflated_size) {
307  frame->pict_type = AV_PICTURE_TYPE_I;
308  frame->key_frame = 1;
309  } else {
310  frame->pict_type = AV_PICTURE_TYPE_P;
311  }
312  if (avctx->pix_fmt == AV_PIX_FMT_PAL8) {
313  const uint8_t *pal = av_packet_get_side_data(avpkt,
315  NULL);
316  if (pal) {
317  frame->palette_has_changed = 1;
318  memcpy(ctx->pal, pal, AVPALETTE_SIZE);
319  }
320  memcpy (frame->data[1], ctx->pal, AVPALETTE_SIZE);
321  }
322  *got_frame = 1;
323 
324 end:
325  av_free(inflated_tiles);
326  return ret;
327 }
328 
330  .name = "rscc",
331  .long_name = NULL_IF_CONFIG_SMALL("innoHeim/Rsupport Screen Capture Codec"),
332  .type = AVMEDIA_TYPE_VIDEO,
333  .id = AV_CODEC_ID_RSCC,
334  .init = rscc_init,
335  .decode = rscc_decode_frame,
336  .close = rscc_close,
337  .priv_data_size = sizeof(RsccContext),
338  .capabilities = AV_CODEC_CAP_DR1,
339  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
341 };
#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:65
#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:184
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:116
int size
Definition: avcodec.h:1602
int component_size
Definition: rscc.c:60
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1904
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:68
AVCodec.
Definition: avcodec.h:3600
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:145
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:73
#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:383
static AVFrame * frame
uint8_t * data
Definition: avcodec.h:1601
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:3070
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define AVERROR(e)
Definition: error.h:43
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:164
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:158
uint8_t * inflated_buf
Definition: rscc.c:64
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
packed BGRA 8:8:8:8, 32bpp, BGRABGRA...
Definition: pixfmt.h:96
#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:3607
static int rscc_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: rscc.c:137
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:499
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:251
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: utils.c:996
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:258
int width
picture width / height.
Definition: avcodec.h:1863
Definition: rscc.c:50
AVFormatContext * ctx
Definition: movenc.c:48
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:65
uint32_t pal[AVPALETTE_COUNT]
Definition: rscc.c:61
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:215
main external API structure.
Definition: avcodec.h:1676
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:1708
int h
Definition: rscc.c:52
AVCodec ff_rscc_decoder
Definition: rscc.c:329
static av_cold int rscc_close(AVCodecContext *avctx)
Definition: rscc.c:126
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:332
packed BGR 8:8:8, 32bpp, BGRXBGRX... X=unused/undefined
Definition: pixfmt.h:254
int w
Definition: rscc.c:52
#define AVPALETTE_COUNT
Definition: pixfmt.h:33
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:198
common internal api header.
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:71
void * priv_data
Definition: avcodec.h:1718
#define av_free(p)
int pixels
Definition: avisynth_c.h:429
int len
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:253
int y
Definition: rscc.c:51
#define av_freep(p)
uint8_t * av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type, int *size)
Get side information from packet.
Definition: avpacket.c:338
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:287
#define MKTAG(a, b, c, d)
Definition: common.h:342
This structure stores compressed data.
Definition: avcodec.h:1578
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:959
Predicted.
Definition: avutil.h:269