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qtrle.c
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1 /*
2  * Quicktime Animation (RLE) Video Decoder
3  * Copyright (c) 2004 The FFmpeg Project
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  * QT RLE Video Decoder by Mike Melanson (melanson@pcisys.net)
25  * For more information about the QT RLE format, visit:
26  * http://www.pcisys.net/~melanson/codecs/
27  *
28  * The QT RLE decoder has seven modes of operation:
29  * 1, 2, 4, 8, 16, 24, and 32 bits per pixel. For modes 1, 2, 4, and 8
30  * the decoder outputs PAL8 colorspace data. 16-bit data yields RGB555
31  * data. 24-bit data is RGB24 and 32-bit data is RGB32.
32  */
33 
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <string.h>
37 
38 #include "avcodec.h"
39 #include "bytestream.h"
40 #include "internal.h"
41 
42 typedef struct QtrleContext {
45 
47  uint32_t pal[256];
48 } QtrleContext;
49 
50 #define CHECK_PIXEL_PTR(n) \
51  if ((pixel_ptr + n > pixel_limit) || (pixel_ptr + n < 0)) { \
52  av_log (s->avctx, AV_LOG_ERROR, "Problem: pixel_ptr = %d, pixel_limit = %d\n",\
53  pixel_ptr + n, pixel_limit); \
54  return; \
55  } \
56 
57 static void qtrle_decode_1bpp(QtrleContext *s, int row_ptr, int lines_to_change)
58 {
59  int rle_code;
60  int pixel_ptr;
61  int row_inc = s->frame->linesize[0];
62  uint8_t pi0, pi1; /* 2 8-pixel values */
63  uint8_t *rgb = s->frame->data[0];
64  int pixel_limit = s->frame->linesize[0] * s->avctx->height;
65  int skip;
66  /* skip & 0x80 appears to mean 'start a new line', which can be interpreted
67  * as 'go to next line' during the decoding of a frame but is 'go to first
68  * line' at the beginning. Since we always interpret it as 'go to next line'
69  * in the decoding loop (which makes code simpler/faster), the first line
70  * would not be counted, so we count one more.
71  * See: https://trac.ffmpeg.org/ticket/226
72  * In the following decoding loop, row_ptr will be the position of the
73  * current row. */
74 
75  row_ptr -= row_inc;
76  pixel_ptr = row_ptr;
77  lines_to_change++;
78  while (lines_to_change) {
79  skip = bytestream2_get_byte(&s->g);
80  rle_code = (int8_t)bytestream2_get_byte(&s->g);
81  if (rle_code == 0)
82  break;
83  if(skip & 0x80) {
84  lines_to_change--;
85  row_ptr += row_inc;
86  pixel_ptr = row_ptr + 2 * (skip & 0x7f);
87  } else
88  pixel_ptr += 2 * skip;
89  CHECK_PIXEL_PTR(0); /* make sure pixel_ptr is positive */
90 
91  if(rle_code == -1)
92  continue;
93 
94  if (rle_code < 0) {
95  /* decode the run length code */
96  rle_code = -rle_code;
97  /* get the next 2 bytes from the stream, treat them as groups
98  * of 8 pixels, and output them rle_code times */
99 
100  pi0 = bytestream2_get_byte(&s->g);
101  pi1 = bytestream2_get_byte(&s->g);
102  CHECK_PIXEL_PTR(rle_code * 2);
103 
104  while (rle_code--) {
105  rgb[pixel_ptr++] = pi0;
106  rgb[pixel_ptr++] = pi1;
107  }
108  } else {
109  /* copy the same pixel directly to output 2 times */
110  rle_code *= 2;
111  CHECK_PIXEL_PTR(rle_code);
112 
113  bytestream2_get_buffer(&s->g, &rgb[pixel_ptr], rle_code);
114  pixel_ptr += rle_code;
115  }
116  }
117 }
118 
119 static inline void qtrle_decode_2n4bpp(QtrleContext *s, int row_ptr,
120  int lines_to_change, int bpp)
121 {
122  int rle_code, i;
123  int pixel_ptr;
124  int row_inc = s->frame->linesize[0];
125  uint8_t pi[16]; /* 16 palette indices */
126  uint8_t *rgb = s->frame->data[0];
127  int pixel_limit = s->frame->linesize[0] * s->avctx->height;
128  int num_pixels = (bpp == 4) ? 8 : 16;
129 
130  while (lines_to_change--) {
131  pixel_ptr = row_ptr + (num_pixels * (bytestream2_get_byte(&s->g) - 1));
132  CHECK_PIXEL_PTR(0);
133 
134  while ((rle_code = (int8_t)bytestream2_get_byte(&s->g)) != -1) {
135  if (rle_code == 0) {
136  /* there's another skip code in the stream */
137  pixel_ptr += (num_pixels * (bytestream2_get_byte(&s->g) - 1));
138  CHECK_PIXEL_PTR(0); /* make sure pixel_ptr is positive */
139  } else if (rle_code < 0) {
140  /* decode the run length code */
141  rle_code = -rle_code;
142  /* get the next 4 bytes from the stream, treat them as palette
143  * indexes, and output them rle_code times */
144  for (i = num_pixels-1; i >= 0; i--) {
145  pi[num_pixels-1-i] = (bytestream2_peek_byte(&s->g) >> ((i*bpp) & 0x07)) & ((1<<bpp)-1);
146  bytestream2_skip(&s->g, ((i & ((num_pixels>>2)-1)) == 0));
147  }
148  CHECK_PIXEL_PTR(rle_code * num_pixels);
149  while (rle_code--) {
150  memcpy(&rgb[pixel_ptr], &pi, num_pixels);
151  pixel_ptr += num_pixels;
152  }
153  } else {
154  /* copy the same pixel directly to output 4 times */
155  rle_code *= 4;
156  CHECK_PIXEL_PTR(rle_code*(num_pixels>>2));
157  while (rle_code--) {
158  if(bpp == 4) {
159  int x = bytestream2_get_byte(&s->g);
160  rgb[pixel_ptr++] = (x >> 4) & 0x0f;
161  rgb[pixel_ptr++] = x & 0x0f;
162  } else {
163  int x = bytestream2_get_byte(&s->g);
164  rgb[pixel_ptr++] = (x >> 6) & 0x03;
165  rgb[pixel_ptr++] = (x >> 4) & 0x03;
166  rgb[pixel_ptr++] = (x >> 2) & 0x03;
167  rgb[pixel_ptr++] = x & 0x03;
168  }
169  }
170  }
171  }
172  row_ptr += row_inc;
173  }
174 }
175 
176 static void qtrle_decode_8bpp(QtrleContext *s, int row_ptr, int lines_to_change)
177 {
178  int rle_code;
179  int pixel_ptr;
180  int row_inc = s->frame->linesize[0];
181  uint8_t pi1, pi2, pi3, pi4; /* 4 palette indexes */
182  uint8_t *rgb = s->frame->data[0];
183  int pixel_limit = s->frame->linesize[0] * s->avctx->height;
184 
185  while (lines_to_change--) {
186  pixel_ptr = row_ptr + (4 * (bytestream2_get_byte(&s->g) - 1));
187  CHECK_PIXEL_PTR(0);
188 
189  while ((rle_code = (int8_t)bytestream2_get_byte(&s->g)) != -1) {
190  if (rle_code == 0) {
191  /* there's another skip code in the stream */
192  pixel_ptr += (4 * (bytestream2_get_byte(&s->g) - 1));
193  CHECK_PIXEL_PTR(0); /* make sure pixel_ptr is positive */
194  } else if (rle_code < 0) {
195  /* decode the run length code */
196  rle_code = -rle_code;
197  /* get the next 4 bytes from the stream, treat them as palette
198  * indexes, and output them rle_code times */
199  pi1 = bytestream2_get_byte(&s->g);
200  pi2 = bytestream2_get_byte(&s->g);
201  pi3 = bytestream2_get_byte(&s->g);
202  pi4 = bytestream2_get_byte(&s->g);
203 
204  CHECK_PIXEL_PTR(rle_code * 4);
205 
206  while (rle_code--) {
207  rgb[pixel_ptr++] = pi1;
208  rgb[pixel_ptr++] = pi2;
209  rgb[pixel_ptr++] = pi3;
210  rgb[pixel_ptr++] = pi4;
211  }
212  } else {
213  /* copy the same pixel directly to output 4 times */
214  rle_code *= 4;
215  CHECK_PIXEL_PTR(rle_code);
216 
217  bytestream2_get_buffer(&s->g, &rgb[pixel_ptr], rle_code);
218  pixel_ptr += rle_code;
219  }
220  }
221  row_ptr += row_inc;
222  }
223 }
224 
225 static void qtrle_decode_16bpp(QtrleContext *s, int row_ptr, int lines_to_change)
226 {
227  int rle_code;
228  int pixel_ptr;
229  int row_inc = s->frame->linesize[0];
230  uint16_t rgb16;
231  uint8_t *rgb = s->frame->data[0];
232  int pixel_limit = s->frame->linesize[0] * s->avctx->height;
233 
234  while (lines_to_change--) {
235  pixel_ptr = row_ptr + (bytestream2_get_byte(&s->g) - 1) * 2;
236  CHECK_PIXEL_PTR(0);
237 
238  while ((rle_code = (int8_t)bytestream2_get_byte(&s->g)) != -1) {
239  if (rle_code == 0) {
240  /* there's another skip code in the stream */
241  pixel_ptr += (bytestream2_get_byte(&s->g) - 1) * 2;
242  CHECK_PIXEL_PTR(0); /* make sure pixel_ptr is positive */
243  } else if (rle_code < 0) {
244  /* decode the run length code */
245  rle_code = -rle_code;
246  rgb16 = bytestream2_get_be16(&s->g);
247 
248  CHECK_PIXEL_PTR(rle_code * 2);
249 
250  while (rle_code--) {
251  *(uint16_t *)(&rgb[pixel_ptr]) = rgb16;
252  pixel_ptr += 2;
253  }
254  } else {
255  CHECK_PIXEL_PTR(rle_code * 2);
256 
257  /* copy pixels directly to output */
258  while (rle_code--) {
259  rgb16 = bytestream2_get_be16(&s->g);
260  *(uint16_t *)(&rgb[pixel_ptr]) = rgb16;
261  pixel_ptr += 2;
262  }
263  }
264  }
265  row_ptr += row_inc;
266  }
267 }
268 
269 static void qtrle_decode_24bpp(QtrleContext *s, int row_ptr, int lines_to_change)
270 {
271  int rle_code;
272  int pixel_ptr;
273  int row_inc = s->frame->linesize[0];
274  uint8_t r, g, b;
275  uint8_t *rgb = s->frame->data[0];
276  int pixel_limit = s->frame->linesize[0] * s->avctx->height;
277 
278  while (lines_to_change--) {
279  pixel_ptr = row_ptr + (bytestream2_get_byte(&s->g) - 1) * 3;
280  CHECK_PIXEL_PTR(0);
281 
282  while ((rle_code = (int8_t)bytestream2_get_byte(&s->g)) != -1) {
283  if (rle_code == 0) {
284  /* there's another skip code in the stream */
285  pixel_ptr += (bytestream2_get_byte(&s->g) - 1) * 3;
286  CHECK_PIXEL_PTR(0); /* make sure pixel_ptr is positive */
287  } else if (rle_code < 0) {
288  /* decode the run length code */
289  rle_code = -rle_code;
290  r = bytestream2_get_byte(&s->g);
291  g = bytestream2_get_byte(&s->g);
292  b = bytestream2_get_byte(&s->g);
293 
294  CHECK_PIXEL_PTR(rle_code * 3);
295 
296  while (rle_code--) {
297  rgb[pixel_ptr++] = r;
298  rgb[pixel_ptr++] = g;
299  rgb[pixel_ptr++] = b;
300  }
301  } else {
302  CHECK_PIXEL_PTR(rle_code * 3);
303 
304  /* copy pixels directly to output */
305  while (rle_code--) {
306  rgb[pixel_ptr++] = bytestream2_get_byte(&s->g);
307  rgb[pixel_ptr++] = bytestream2_get_byte(&s->g);
308  rgb[pixel_ptr++] = bytestream2_get_byte(&s->g);
309  }
310  }
311  }
312  row_ptr += row_inc;
313  }
314 }
315 
316 static void qtrle_decode_32bpp(QtrleContext *s, int row_ptr, int lines_to_change)
317 {
318  int rle_code;
319  int pixel_ptr;
320  int row_inc = s->frame->linesize[0];
321  unsigned int argb;
322  uint8_t *rgb = s->frame->data[0];
323  int pixel_limit = s->frame->linesize[0] * s->avctx->height;
324 
325  while (lines_to_change--) {
326  pixel_ptr = row_ptr + (bytestream2_get_byte(&s->g) - 1) * 4;
327  CHECK_PIXEL_PTR(0);
328 
329  while ((rle_code = (int8_t)bytestream2_get_byte(&s->g)) != -1) {
330  if (rle_code == 0) {
331  /* there's another skip code in the stream */
332  pixel_ptr += (bytestream2_get_byte(&s->g) - 1) * 4;
333  CHECK_PIXEL_PTR(0); /* make sure pixel_ptr is positive */
334  } else if (rle_code < 0) {
335  /* decode the run length code */
336  rle_code = -rle_code;
337  argb = bytestream2_get_be32(&s->g);
338 
339  CHECK_PIXEL_PTR(rle_code * 4);
340 
341  while (rle_code--) {
342  AV_WN32A(rgb + pixel_ptr, argb);
343  pixel_ptr += 4;
344  }
345  } else {
346  CHECK_PIXEL_PTR(rle_code * 4);
347 
348  /* copy pixels directly to output */
349  while (rle_code--) {
350  argb = bytestream2_get_be32(&s->g);
351  AV_WN32A(rgb + pixel_ptr, argb);
352  pixel_ptr += 4;
353  }
354  }
355  }
356  row_ptr += row_inc;
357  }
358 }
359 
361 {
362  QtrleContext *s = avctx->priv_data;
363 
364  s->avctx = avctx;
365  switch (avctx->bits_per_coded_sample) {
366  case 1:
367  case 33:
368  avctx->pix_fmt = AV_PIX_FMT_MONOWHITE;
369  break;
370 
371  case 2:
372  case 4:
373  case 8:
374  case 34:
375  case 36:
376  case 40:
377  avctx->pix_fmt = AV_PIX_FMT_PAL8;
378  break;
379 
380  case 16:
381  avctx->pix_fmt = AV_PIX_FMT_RGB555;
382  break;
383 
384  case 24:
385  avctx->pix_fmt = AV_PIX_FMT_RGB24;
386  break;
387 
388  case 32:
389  avctx->pix_fmt = AV_PIX_FMT_RGB32;
390  break;
391 
392  default:
393  av_log (avctx, AV_LOG_ERROR, "Unsupported colorspace: %d bits/sample?\n",
394  avctx->bits_per_coded_sample);
395  return AVERROR_INVALIDDATA;
396  }
397 
398  s->frame = av_frame_alloc();
399  if (!s->frame)
400  return AVERROR(ENOMEM);
401 
402  return 0;
403 }
404 
406  void *data, int *got_frame,
407  AVPacket *avpkt)
408 {
409  QtrleContext *s = avctx->priv_data;
410  int header, start_line;
411  int height, row_ptr;
412  int has_palette = 0;
413  int ret;
414 
415  bytestream2_init(&s->g, avpkt->data, avpkt->size);
416  if ((ret = ff_reget_buffer(avctx, s->frame)) < 0)
417  return ret;
418 
419  /* check if this frame is even supposed to change */
420  if (avpkt->size < 8)
421  goto done;
422 
423  /* start after the chunk size */
424  bytestream2_seek(&s->g, 4, SEEK_SET);
425 
426  /* fetch the header */
427  header = bytestream2_get_be16(&s->g);
428 
429  /* if a header is present, fetch additional decoding parameters */
430  if (header & 0x0008) {
431  if (avpkt->size < 14)
432  goto done;
433  start_line = bytestream2_get_be16(&s->g);
434  bytestream2_skip(&s->g, 2);
435  height = bytestream2_get_be16(&s->g);
436  bytestream2_skip(&s->g, 2);
437  if (height > s->avctx->height - start_line)
438  goto done;
439  } else {
440  start_line = 0;
441  height = s->avctx->height;
442  }
443  row_ptr = s->frame->linesize[0] * start_line;
444 
445  switch (avctx->bits_per_coded_sample) {
446  case 1:
447  case 33:
448  qtrle_decode_1bpp(s, row_ptr, height);
449  break;
450 
451  case 2:
452  case 34:
453  qtrle_decode_2n4bpp(s, row_ptr, height, 2);
454  has_palette = 1;
455  break;
456 
457  case 4:
458  case 36:
459  qtrle_decode_2n4bpp(s, row_ptr, height, 4);
460  has_palette = 1;
461  break;
462 
463  case 8:
464  case 40:
465  qtrle_decode_8bpp(s, row_ptr, height);
466  has_palette = 1;
467  break;
468 
469  case 16:
470  qtrle_decode_16bpp(s, row_ptr, height);
471  break;
472 
473  case 24:
474  qtrle_decode_24bpp(s, row_ptr, height);
475  break;
476 
477  case 32:
478  qtrle_decode_32bpp(s, row_ptr, height);
479  break;
480 
481  default:
482  av_log (s->avctx, AV_LOG_ERROR, "Unsupported colorspace: %d bits/sample?\n",
483  avctx->bits_per_coded_sample);
484  break;
485  }
486 
487  if(has_palette) {
488  const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL);
489 
490  if (pal) {
491  s->frame->palette_has_changed = 1;
492  memcpy(s->pal, pal, AVPALETTE_SIZE);
493  }
494 
495  /* make the palette available on the way out */
496  memcpy(s->frame->data[1], s->pal, AVPALETTE_SIZE);
497  }
498 
499 done:
500  if ((ret = av_frame_ref(data, s->frame)) < 0)
501  return ret;
502  *got_frame = 1;
503 
504  /* always report that the buffer was completely consumed */
505  return avpkt->size;
506 }
507 
509 {
510  QtrleContext *s = avctx->priv_data;
511 
512  av_frame_free(&s->frame);
513 
514  return 0;
515 }
516 
518  .name = "qtrle",
519  .long_name = NULL_IF_CONFIG_SMALL("QuickTime Animation (RLE) video"),
520  .type = AVMEDIA_TYPE_VIDEO,
521  .id = AV_CODEC_ID_QTRLE,
522  .priv_data_size = sizeof(QtrleContext),
524  .close = qtrle_decode_end,
526  .capabilities = CODEC_CAP_DR1,
527 };