Libav
qtrleenc.c
Go to the documentation of this file.
1 /*
2  * Quicktime Animation (RLE) Video Encoder
3  * Copyright (C) 2007 Clemens Fruhwirth
4  * Copyright (C) 2007 Alexis Ballier
5  *
6  * This file is based on flashsvenc.c.
7  *
8  * This file is part of Libav.
9  *
10  * Libav is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU Lesser General Public
12  * License as published by the Free Software Foundation; either
13  * version 2.1 of the License, or (at your option) any later version.
14  *
15  * Libav is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18  * Lesser General Public License for more details.
19  *
20  * You should have received a copy of the GNU Lesser General Public
21  * License along with Libav; if not, write to the Free Software
22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23  */
24 
25 #include "libavutil/imgutils.h"
26 #include "avcodec.h"
27 #include "bytestream.h"
28 #include "internal.h"
29 
31 #define MAX_RLE_BULK 127
32 
33 #define MAX_RLE_REPEAT 128
34 
35 #define MAX_RLE_SKIP 254
36 
37 typedef struct QtrleEncContext {
41  unsigned int max_buf_size;
51  signed char *rlecode_table;
60 
62  int key_frame;
64 
66 {
67  QtrleEncContext *s = avctx->priv_data;
68 
72  av_free(s->skip_table);
73  return 0;
74 }
75 
77 {
78  QtrleEncContext *s = avctx->priv_data;
79 
80  if (av_image_check_size(avctx->width, avctx->height, 0, avctx) < 0) {
81  return -1;
82  }
83  s->avctx=avctx;
84 
85  switch (avctx->pix_fmt) {
87  s->pixel_size = 2;
88  break;
89  case AV_PIX_FMT_RGB24:
90  s->pixel_size = 3;
91  break;
92  case AV_PIX_FMT_ARGB:
93  s->pixel_size = 4;
94  break;
95  default:
96  av_log(avctx, AV_LOG_ERROR, "Unsupported colorspace.\n");
97  break;
98  }
99  avctx->bits_per_coded_sample = s->pixel_size*8;
100 
102  s->skip_table = av_mallocz(s->avctx->width);
103  s->length_table = av_mallocz((s->avctx->width + 1)*sizeof(int));
104  if (!s->skip_table || !s->length_table || !s->rlecode_table) {
105  av_log(avctx, AV_LOG_ERROR, "Error allocating memory.\n");
106  return -1;
107  }
109  if (!s->previous_frame) {
110  av_log(avctx, AV_LOG_ERROR, "Error allocating picture\n");
111  return -1;
112  }
113 
114  s->max_buf_size = s->avctx->width*s->avctx->height*s->pixel_size*2 /* image base material */
115  + 15 /* header + footer */
116  + s->avctx->height*2 /* skip code+rle end */
117  + s->avctx->width/MAX_RLE_BULK + 1 /* rle codes */;
118 
119  return 0;
120 }
121 
125 static void qtrle_encode_line(QtrleEncContext *s, const AVFrame *p, int line, uint8_t **buf)
126 {
127  int width=s->avctx->width;
128  int i;
129  signed char rlecode;
130 
131  /* We will use it to compute the best bulk copy sequence */
132  unsigned int bulkcount;
133  /* This will be the number of pixels equal to the previous frame one's
134  * starting from the ith pixel */
135  unsigned int skipcount;
136  /* This will be the number of consecutive equal pixels in the current
137  * frame, starting from the ith one also */
138  unsigned int repeatcount;
139 
140  /* The cost of the three different possibilities */
141  int total_bulk_cost;
142  int total_skip_cost;
143  int total_repeat_cost;
144 
145  int temp_cost;
146  int j;
147 
148  uint8_t *this_line = p-> data[0] + line*p-> linesize[0] +
149  (width - 1)*s->pixel_size;
150  uint8_t *prev_line = s->previous_frame->data[0] + line * s->previous_frame->linesize[0] +
151  (width - 1)*s->pixel_size;
152 
153  s->length_table[width] = 0;
154  skipcount = 0;
155 
156  for (i = width - 1; i >= 0; i--) {
157 
158  if (!s->key_frame && !memcmp(this_line, prev_line, s->pixel_size))
159  skipcount = FFMIN(skipcount + 1, MAX_RLE_SKIP);
160  else
161  skipcount = 0;
162 
163  total_skip_cost = s->length_table[i + skipcount] + 2;
164  s->skip_table[i] = skipcount;
165 
166 
167  if (i < width - 1 && !memcmp(this_line, this_line + s->pixel_size, s->pixel_size))
168  repeatcount = FFMIN(repeatcount + 1, MAX_RLE_REPEAT);
169  else
170  repeatcount = 1;
171 
172  total_repeat_cost = s->length_table[i + repeatcount] + 1 + s->pixel_size;
173 
174  /* skip code is free for the first pixel, it costs one byte for repeat and bulk copy
175  * so let's make it aware */
176  if (i == 0) {
177  total_skip_cost--;
178  total_repeat_cost++;
179  }
180 
181  if (repeatcount > 1 && (skipcount == 0 || total_repeat_cost < total_skip_cost)) {
182  /* repeat is the best */
183  s->length_table[i] = total_repeat_cost;
184  s->rlecode_table[i] = -repeatcount;
185  }
186  else if (skipcount > 0) {
187  /* skip is the best choice here */
188  s->length_table[i] = total_skip_cost;
189  s->rlecode_table[i] = 0;
190  }
191  else {
192  /* We cannot do neither skip nor repeat
193  * thus we search for the best bulk copy to do */
194 
195  int limit = FFMIN(width - i, MAX_RLE_BULK);
196 
197  temp_cost = 1 + s->pixel_size + !i;
198  total_bulk_cost = INT_MAX;
199 
200  for (j = 1; j <= limit; j++) {
201  if (s->length_table[i + j] + temp_cost < total_bulk_cost) {
202  /* We have found a better bulk copy ... */
203  total_bulk_cost = s->length_table[i + j] + temp_cost;
204  bulkcount = j;
205  }
206  temp_cost += s->pixel_size;
207  }
208 
209  s->length_table[i] = total_bulk_cost;
210  s->rlecode_table[i] = bulkcount;
211  }
212 
213  this_line -= s->pixel_size;
214  prev_line -= s->pixel_size;
215  }
216 
217  /* Good! Now we have the best sequence for this line, let's output it. */
218 
219  /* We do a special case for the first pixel so that we avoid testing it in
220  * the whole loop */
221 
222  i=0;
223  this_line = p-> data[0] + line*p->linesize[0];
224 
225  if (s->rlecode_table[0] == 0) {
226  bytestream_put_byte(buf, s->skip_table[0] + 1);
227  i += s->skip_table[0];
228  }
229  else bytestream_put_byte(buf, 1);
230 
231 
232  while (i < width) {
233  rlecode = s->rlecode_table[i];
234  bytestream_put_byte(buf, rlecode);
235  if (rlecode == 0) {
236  /* Write a skip sequence */
237  bytestream_put_byte(buf, s->skip_table[i] + 1);
238  i += s->skip_table[i];
239  }
240  else if (rlecode > 0) {
241  /* bulk copy */
242  bytestream_put_buffer(buf, this_line + i*s->pixel_size, rlecode*s->pixel_size);
243  i += rlecode;
244  }
245  else {
246  /* repeat the bits */
247  bytestream_put_buffer(buf, this_line + i*s->pixel_size, s->pixel_size);
248  i -= rlecode;
249  }
250  }
251  bytestream_put_byte(buf, -1); // end RLE line
252 }
253 
255 static int encode_frame(QtrleEncContext *s, const AVFrame *p, uint8_t *buf)
256 {
257  int i;
258  int start_line = 0;
259  int end_line = s->avctx->height;
260  uint8_t *orig_buf = buf;
261 
262  if (!s->key_frame) {
263  unsigned line_size = s->avctx->width * s->pixel_size;
264  for (start_line = 0; start_line < s->avctx->height; start_line++)
265  if (memcmp(p->data[0] + start_line*p->linesize[0],
266  s->previous_frame->data[0] + start_line * s->previous_frame->linesize[0],
267  line_size))
268  break;
269 
270  for (end_line=s->avctx->height; end_line > start_line; end_line--)
271  if (memcmp(p->data[0] + (end_line - 1)*p->linesize[0],
272  s->previous_frame->data[0] + (end_line - 1) * s->previous_frame->linesize[0],
273  line_size))
274  break;
275  }
276 
277  bytestream_put_be32(&buf, 0); // CHUNK SIZE, patched later
278 
279  if ((start_line == 0 && end_line == s->avctx->height) || start_line == s->avctx->height)
280  bytestream_put_be16(&buf, 0); // header
281  else {
282  bytestream_put_be16(&buf, 8); // header
283  bytestream_put_be16(&buf, start_line); // starting line
284  bytestream_put_be16(&buf, 0); // unknown
285  bytestream_put_be16(&buf, end_line - start_line); // lines to update
286  bytestream_put_be16(&buf, 0); // unknown
287  }
288  for (i = start_line; i < end_line; i++)
289  qtrle_encode_line(s, p, i, &buf);
290 
291  bytestream_put_byte(&buf, 0); // zero skip code = frame finished
292  AV_WB32(orig_buf, buf - orig_buf); // patch the chunk size
293  return buf - orig_buf;
294 }
295 
297  const AVFrame *pict, int *got_packet)
298 {
299  QtrleEncContext * const s = avctx->priv_data;
300 #if FF_API_CODED_FRAME
301  enum AVPictureType pict_type;
302 #endif
303  int ret;
304 
305  if ((ret = ff_alloc_packet(pkt, s->max_buf_size)) < 0) {
306  /* Upper bound check for compressed data */
307  av_log(avctx, AV_LOG_ERROR, "Error getting output packet of size %d.\n", s->max_buf_size);
308  return ret;
309  }
310 
311  if (avctx->gop_size == 0 || (s->avctx->frame_number % avctx->gop_size) == 0) {
312  /* I-Frame */
313 #if FF_API_CODED_FRAME
314  pict_type = AV_PICTURE_TYPE_I;
315 #endif
316  s->key_frame = 1;
317  } else {
318  /* P-Frame */
319 #if FF_API_CODED_FRAME
320  pict_type = AV_PICTURE_TYPE_P;
321 #endif
322  s->key_frame = 0;
323  }
324 
325  pkt->size = encode_frame(s, pict, pkt->data);
326 
327  /* save the current frame */
329  ret = av_frame_ref(s->previous_frame, pict);
330  if (ret < 0) {
331  av_log(avctx, AV_LOG_ERROR, "cannot add reference\n");
332  return ret;
333  }
334 
335 #if FF_API_CODED_FRAME
337  avctx->coded_frame->key_frame = s->key_frame;
338  avctx->coded_frame->pict_type = pict_type;
340 #endif
341 
342  if (s->key_frame)
343  pkt->flags |= AV_PKT_FLAG_KEY;
344  *got_packet = 1;
345 
346  return 0;
347 }
348 
350  .name = "qtrle",
351  .long_name = NULL_IF_CONFIG_SMALL("QuickTime Animation (RLE) video"),
352  .type = AVMEDIA_TYPE_VIDEO,
353  .id = AV_CODEC_ID_QTRLE,
354  .priv_data_size = sizeof(QtrleEncContext),
356  .encode2 = qtrle_encode_frame,
357  .close = qtrle_encode_end,
358  .pix_fmts = (const enum AVPixelFormat[]){
360  },
361 };
int * length_table
This array will contain the length of the best rle encoding of the line starting at ith pixel...
Definition: qtrleenc.c:55
This structure describes decoded (raw) audio or video data.
Definition: frame.h:140
misc image utilities
packed RGB 8:8:8, 24bpp, RGBRGB...
Definition: pixfmt.h:61
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)
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1621
static int encode_frame(QtrleEncContext *s, const AVFrame *p, uint8_t *buf)
Encode frame including header.
Definition: qtrleenc.c:255
AVCodec.
Definition: avcodec.h:3120
#define AV_WB32(p, val)
Definition: intreadwrite.h:246
static av_cold int qtrle_encode_end(AVCodecContext *avctx)
Definition: qtrleenc.c:65
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
AVCodecContext * avctx
Definition: qtrleenc.c:38
int key_frame
Encoded frame is a key frame.
Definition: qtrleenc.c:62
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
uint8_t * skip_table
Will contain at ith position the number of consecutive pixels equal to the previous frame starting fr...
Definition: qtrleenc.c:59
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2769
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1378
#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
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:80
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:148
#define MAX_RLE_BULK
Maximum RLE code for bulk copy.
Definition: qtrleenc.c:31
static int qtrle_encode_frame(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *pict, int *got_packet)
Definition: qtrleenc.c:296
Definition: graph2dot.c:48
const char * name
Name of the codec implementation.
Definition: avcodec.h:3127
#define MAX_RLE_SKIP
Maximum RLE code for skip.
Definition: qtrleenc.c:35
packed ARGB 8:8:8:8, 32bpp, ARGBARGB...
Definition: pixfmt.h:89
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1352
static av_cold int qtrle_encode_init(AVCodecContext *avctx)
Definition: qtrleenc.c:76
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
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:201
#define FFMIN(a, b)
Definition: common.h:66
int width
picture width / height.
Definition: avcodec.h:1580
AVFrame * previous_frame
Definition: qtrleenc.c:40
#define MAX_RLE_REPEAT
Maximum RLE code for repeat.
Definition: qtrleenc.c:33
int ff_alloc_packet(AVPacket *avpkt, int size)
Check AVPacket size and/or allocate data.
Definition: utils.c:1211
unsigned int max_buf_size
Definition: qtrleenc.c:41
static int width
Definition: utils.c:156
Libavcodec external API header.
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
AVPictureType
Definition: avutil.h:259
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:257
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:302
packed RGB 5:5:5, 16bpp, (msb)1A 5R 5G 5B(lsb), big-endian, most significant bit to 0 ...
Definition: pixfmt.h:111
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:146
static void qtrle_encode_line(QtrleEncContext *s, const AVFrame *p, int line, uint8_t **buf)
Compute the best RLE sequence for a line.
Definition: qtrleenc.c:125
int gop_size
the number of pictures in a group of pictures, or 0 for intra_only
Definition: avcodec.h:1606
#define FF_DISABLE_DEPRECATION_WARNINGS
Definition: internal.h:77
common internal api header.
attribute_deprecated AVFrame * coded_frame
the picture in the bitstream
Definition: avcodec.h:2797
static av_cold int init(AVCodecParserContext *s)
Definition: h264_parser.c:582
static av_always_inline void bytestream_put_buffer(uint8_t **b, const uint8_t *src, unsigned int size)
Definition: bytestream.h:365
void * priv_data
Definition: avcodec.h:1451
signed char * rlecode_table
This array will contain at ith position the value of the best RLE code if the line started at pixel i...
Definition: qtrleenc.c:51
#define FF_ENABLE_DEPRECATION_WARNINGS
Definition: internal.h:78
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:196
int frame_number
Frame counter, set by libavcodec.
Definition: avcodec.h:2183
AVCodec ff_qtrle_encoder
Definition: qtrleenc.c:349
AVPixelFormat
Pixel format.
Definition: pixfmt.h:57
This structure stores compressed data.
Definition: avcodec.h:1323
void * av_mallocz(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:211
Predicted.
Definition: avutil.h:261