Libav
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 Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
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 
62  /* zlib interaction */
64  uLongf inflated_size;
65 } RsccContext;
66 
67 static av_cold int rscc_init(AVCodecContext *avctx)
68 {
69  RsccContext *ctx = avctx->priv_data;
70 
71  /* These needs to be set to estimate uncompressed buffer */
72  int ret = av_image_check_size(avctx->width, avctx->height, 0, avctx);
73  if (ret < 0) {
74  av_log(avctx, AV_LOG_ERROR, "Invalid image size %dx%d.\n",
75  avctx->width, avctx->height);
76  return ret;
77  }
78 
79  /* Allocate reference frame */
80  ctx->reference = av_frame_alloc();
81  if (!ctx->reference)
82  return AVERROR(ENOMEM);
83 
84  /* Get pixel format and the size of the pixel */
85  if (avctx->codec_tag == MKTAG('I', 'S', 'C', 'C')) {
86  avctx->pix_fmt = AV_PIX_FMT_BGRA;
87  ctx->component_size = 4;
88  } else if (avctx->codec_tag == MKTAG('R', 'S', 'C', 'C')) {
89  ctx->component_size = avctx->bits_per_coded_sample / 8;
90  switch (avctx->bits_per_coded_sample) {
91  case 8:
92  avpriv_report_missing_feature(avctx, "8 bits per pixel");
93  return AVERROR_PATCHWELCOME;
94  case 16:
96  break;
97  case 24:
98  avctx->pix_fmt = AV_PIX_FMT_BGR24;
99  break;
100  case 32:
101  avctx->pix_fmt = AV_PIX_FMT_BGRA;
102  break;
103  default:
104  av_log(avctx, AV_LOG_ERROR, "Invalid bits per pixel value (%d)\n",
105  avctx->bits_per_coded_sample);
106  return AVERROR_INVALIDDATA;
107  }
108  } else {
109  av_log(avctx, AV_LOG_ERROR, "Invalid codec tag\n");
110  return AVERROR_INVALIDDATA;
111  }
112 
113  /* Store the value to check for keyframes */
114  ctx->inflated_size = avctx->width * avctx->height * ctx->component_size;
115 
116  /* Allocate maximum size possible, a full frame */
117  ctx->inflated_buf = av_malloc(ctx->inflated_size);
118  if (!ctx->inflated_buf)
119  return AVERROR(ENOMEM);
120 
121  return 0;
122 }
123 
125 {
126  RsccContext *ctx = avctx->priv_data;
127 
128  av_freep(&ctx->tiles);
129  av_freep(&ctx->inflated_buf);
130  av_frame_free(&ctx->reference);
131 
132  return 0;
133 }
134 
135 static int rscc_decode_frame(AVCodecContext *avctx, void *data,
136  int *got_frame, AVPacket *avpkt)
137 {
138  RsccContext *ctx = avctx->priv_data;
139  GetByteContext *gbc = &ctx->gbc;
140  GetByteContext tiles_gbc;
141  AVFrame *frame = data;
142  const uint8_t *pixels, *raw;
143  uint8_t *inflated_tiles = NULL;
144  int tiles_nb, packed_size, pixel_size = 0;
145  int i, ret = 0;
146 
147  bytestream2_init(gbc, avpkt->data, avpkt->size);
148 
149  /* Size check */
150  if (bytestream2_get_bytes_left(gbc) < 12) {
151  av_log(avctx, AV_LOG_ERROR, "Packet too small (%d)\n", avpkt->size);
152  return AVERROR_INVALIDDATA;
153  }
154 
155  /* Read number of tiles, and allocate the array */
156  tiles_nb = bytestream2_get_le16(gbc);
157  av_fast_malloc(&ctx->tiles, &ctx->tiles_size,
158  tiles_nb * sizeof(*ctx->tiles));
159  if (!ctx->tiles) {
160  ret = AVERROR(ENOMEM);
161  goto end;
162  }
163 
164  av_log(avctx, AV_LOG_DEBUG, "Frame with %d tiles.\n", tiles_nb);
165 
166  /* When there are more than 5 tiles, they are packed together with
167  * a size header. When that size does not match the number of tiles
168  * times the tile size, it means it needs to be inflated as well */
169  if (tiles_nb > 5) {
170  uLongf packed_tiles_size;
171 
172  if (tiles_nb < 32)
173  packed_tiles_size = bytestream2_get_byte(gbc);
174  else
175  packed_tiles_size = bytestream2_get_le16(gbc);
176 
177  ff_dlog(avctx, "packed tiles of size %lu.\n", packed_tiles_size);
178 
179  /* If necessary, uncompress tiles, and hijack the bytestream reader */
180  if (packed_tiles_size != tiles_nb * TILE_SIZE) {
181  uLongf length = tiles_nb * TILE_SIZE;
182  inflated_tiles = av_malloc(length);
183  if (!inflated_tiles) {
184  ret = AVERROR(ENOMEM);
185  goto end;
186  }
187 
188  ret = uncompress(inflated_tiles, &length,
189  gbc->buffer, packed_tiles_size);
190  if (ret) {
191  av_log(avctx, AV_LOG_ERROR, "Tile deflate error %d.\n", ret);
192  ret = AVERROR_UNKNOWN;
193  goto end;
194  }
195 
196  /* Skip the compressed tile section in the main byte reader,
197  * and point it to read the newly uncompressed data */
198  bytestream2_skip(gbc, packed_tiles_size);
199  bytestream2_init(&tiles_gbc, inflated_tiles, length);
200  gbc = &tiles_gbc;
201  }
202  }
203 
204  /* Fill in array of tiles, keeping track of how many pixels are updated */
205  for (i = 0; i < tiles_nb; i++) {
206  ctx->tiles[i].x = bytestream2_get_le16(gbc);
207  ctx->tiles[i].w = bytestream2_get_le16(gbc);
208  ctx->tiles[i].y = bytestream2_get_le16(gbc);
209  ctx->tiles[i].h = bytestream2_get_le16(gbc);
210 
211  pixel_size += ctx->tiles[i].w * ctx->tiles[i].h * ctx->component_size;
212 
213  ff_dlog(avctx, "tile %d orig(%d,%d) %dx%d.\n", i,
214  ctx->tiles[i].x, ctx->tiles[i].y,
215  ctx->tiles[i].w, ctx->tiles[i].h);
216 
217  if (ctx->tiles[i].w == 0 || ctx->tiles[i].h == 0) {
218  av_log(avctx, AV_LOG_ERROR,
219  "invalid tile %d at (%d.%d) with size %dx%d.\n", i,
220  ctx->tiles[i].x, ctx->tiles[i].y,
221  ctx->tiles[i].w, ctx->tiles[i].h);
222  ret = AVERROR_INVALIDDATA;
223  goto end;
224  } else if (ctx->tiles[i].x + ctx->tiles[i].w > avctx->width ||
225  ctx->tiles[i].y + ctx->tiles[i].h > avctx->height) {
226  av_log(avctx, AV_LOG_ERROR,
227  "out of bounds tile %d at (%d.%d) with size %dx%d.\n", i,
228  ctx->tiles[i].x, ctx->tiles[i].y,
229  ctx->tiles[i].w, ctx->tiles[i].h);
230  ret = AVERROR_INVALIDDATA;
231  goto end;
232  }
233  }
234 
235  /* Reset the reader in case it had been modified before */
236  gbc = &ctx->gbc;
237 
238  /* Extract how much pixel data the tiles contain */
239  if (pixel_size < 0x100)
240  packed_size = bytestream2_get_byte(gbc);
241  else if (pixel_size < 0x10000)
242  packed_size = bytestream2_get_le16(gbc);
243  else if (pixel_size < 0x1000000)
244  packed_size = bytestream2_get_le24(gbc);
245  else
246  packed_size = bytestream2_get_le32(gbc);
247 
248  ff_dlog(avctx, "pixel_size %d packed_size %d.\n", pixel_size, packed_size);
249 
250  /* Get pixels buffer, it may be deflated or just raw */
251  if (pixel_size == packed_size) {
252  pixels = gbc->buffer;
253  } else {
254  uLongf len = ctx->inflated_size;
255  ret = uncompress(ctx->inflated_buf, &len, gbc->buffer, packed_size);
256  if (ret) {
257  av_log(avctx, AV_LOG_ERROR, "Pixel deflate error %d.\n", ret);
258  ret = AVERROR_UNKNOWN;
259  goto end;
260  }
261  pixels = ctx->inflated_buf;
262  }
263 
264  /* Allocate when needed */
265  ret = ff_reget_buffer(avctx, ctx->reference);
266  if (ret < 0)
267  goto end;
268 
269  /* Pointer to actual pixels, will be updated when data is consumed */
270  raw = pixels;
271  for (i = 0; i < tiles_nb; i++) {
272  uint8_t *dst = ctx->reference->data[0] + ctx->reference->linesize[0] *
273  (avctx->height - ctx->tiles[i].y - 1) +
274  ctx->tiles[i].x * ctx->component_size;
275  av_image_copy_plane(dst, -1 * ctx->reference->linesize[0],
276  raw, ctx->tiles[i].w * ctx->component_size,
277  ctx->tiles[i].w * ctx->component_size,
278  ctx->tiles[i].h);
279  raw += ctx->tiles[i].w * ctx->component_size * ctx->tiles[i].h;
280  }
281 
282  /* Frame is ready to be output */
283  ret = av_frame_ref(frame, ctx->reference);
284  if (ret < 0)
285  goto end;
286 
287  /* Keyframe when the number of pixels updated matches the whole surface */
288  if (pixel_size == ctx->inflated_size) {
289  frame->pict_type = AV_PICTURE_TYPE_I;
290  frame->key_frame = 1;
291  } else {
292  frame->pict_type = AV_PICTURE_TYPE_P;
293  }
294  *got_frame = 1;
295 
296 end:
297  av_free(inflated_tiles);
298  return ret;
299 }
300 
302  .name = "rscc",
303  .long_name = NULL_IF_CONFIG_SMALL("innoHeim/Rsupport Screen Capture Codec"),
304  .type = AVMEDIA_TYPE_VIDEO,
305  .id = AV_CODEC_ID_RSCC,
306  .init = rscc_init,
307  .decode = rscc_decode_frame,
308  .close = rscc_close,
309  .priv_data_size = sizeof(RsccContext),
310  .capabilities = AV_CODEC_CAP_DR1,
311  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
313 };
#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:64
void * av_malloc(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:62
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
This structure describes decoded (raw) audio or video data.
Definition: frame.h:140
misc image utilities
packed RGB 5:5:5, 16bpp, (msb)1A 5R 5G 5B(lsb), little-endian, most significant bit to 0 ...
Definition: pixfmt.h:112
int size
Definition: avcodec.h:1347
av_log(ac->avr, AV_LOG_TRACE, "%d samples - audio_convert: %s to %s (%s)\, len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt), use_generic ? ac->func_descr_generic :ac->func_descr)
int component_size
Definition: rscc.c:60
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1621
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:132
static av_cold int rscc_init(AVCodecContext *avctx)
Definition: rscc.c:67
AVCodec.
Definition: avcodec.h:3120
void av_freep(void *arg)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc() and set the pointer ...
Definition: mem.c:202
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:66
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:68
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:199
const char data[16]
Definition: mxf.c:70
uint8_t * data
Definition: avcodec.h:1346
const uint8_t * buffer
Definition: bytestream.h:33
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2769
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:124
void av_free(void *ptr)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc(). ...
Definition: mem.c:190
#define AVERROR(e)
Definition: error.h:43
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:161
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:80
uint8_t * inflated_buf
Definition: rscc.c:63
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:148
packed BGRA 8:8:8:8, 32bpp, BGRABGRA...
Definition: pixfmt.h:92
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:145
static av_always_inline unsigned int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:151
const char * name
Name of the codec implementation.
Definition: avcodec.h:3127
static int rscc_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: rscc.c:135
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:223
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:672
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:201
int width
picture width / height.
Definition: avcodec.h:1580
Definition: rscc.c:50
AVFormatContext * ctx
Definition: movenc.c:48
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:62
int x
Definition: rscc.c:51
#define AVERROR_PATCHWELCOME
Not yet implemented in Libav, patches welcome.
Definition: error.h:57
NULL
Definition: eval.c:55
Libavcodec external API header.
#define ff_dlog(ctx,...)
Definition: internal.h:60
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:158
main external API structure.
Definition: avcodec.h:1409
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:1441
int h
Definition: rscc.c:52
AVCodec ff_rscc_decoder
Definition: rscc.c:301
static av_cold int rscc_close(AVCodecContext *avctx)
Definition: rscc.c:124
int w
Definition: rscc.c:52
void avpriv_report_missing_feature(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:146
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:394
common internal api header.
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:61
void * priv_data
Definition: avcodec.h:1451
int len
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:196
int y
Definition: rscc.c:51
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:255
#define MKTAG(a, b, c, d)
Definition: common.h:256
This structure stores compressed data.
Definition: avcodec.h:1323
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:838
Predicted.
Definition: avutil.h:261