Libav
qtrleenc.c
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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;
61 
63 {
64  QtrleEncContext *s = avctx->priv_data;
65 
66  av_frame_free(&avctx->coded_frame);
67 
71  av_free(s->skip_table);
72  return 0;
73 }
74 
76 {
77  QtrleEncContext *s = avctx->priv_data;
78 
79  if (av_image_check_size(avctx->width, avctx->height, 0, avctx) < 0) {
80  return -1;
81  }
82  s->avctx=avctx;
83 
84  switch (avctx->pix_fmt) {
86  s->pixel_size = 2;
87  break;
88  case AV_PIX_FMT_RGB24:
89  s->pixel_size = 3;
90  break;
91  case AV_PIX_FMT_ARGB:
92  s->pixel_size = 4;
93  break;
94  default:
95  av_log(avctx, AV_LOG_ERROR, "Unsupported colorspace.\n");
96  break;
97  }
98  avctx->bits_per_coded_sample = s->pixel_size*8;
99 
101  s->skip_table = av_mallocz(s->avctx->width);
102  s->length_table = av_mallocz((s->avctx->width + 1)*sizeof(int));
103  if (!s->skip_table || !s->length_table || !s->rlecode_table) {
104  av_log(avctx, AV_LOG_ERROR, "Error allocating memory.\n");
105  return -1;
106  }
107  if (avpicture_alloc(&s->previous_frame, avctx->pix_fmt, avctx->width, avctx->height) < 0) {
108  av_log(avctx, AV_LOG_ERROR, "Error allocating picture\n");
109  return -1;
110  }
111 
112  s->max_buf_size = s->avctx->width*s->avctx->height*s->pixel_size*2 /* image base material */
113  + 15 /* header + footer */
114  + s->avctx->height*2 /* skip code+rle end */
115  + s->avctx->width/MAX_RLE_BULK + 1 /* rle codes */;
116 
117  avctx->coded_frame = av_frame_alloc();
118  if (!avctx->coded_frame) {
119  qtrle_encode_end(avctx);
120  return AVERROR(ENOMEM);
121  }
122 
123  return 0;
124 }
125 
129 static void qtrle_encode_line(QtrleEncContext *s, const AVFrame *p, int line, uint8_t **buf)
130 {
131  int width=s->avctx->width;
132  int i;
133  signed char rlecode;
134 
135  /* We will use it to compute the best bulk copy sequence */
136  unsigned int bulkcount;
137  /* This will be the number of pixels equal to the preivous frame one's
138  * starting from the ith pixel */
139  unsigned int skipcount;
140  /* This will be the number of consecutive equal pixels in the current
141  * frame, starting from the ith one also */
142  unsigned int repeatcount;
143 
144  /* The cost of the three different possibilities */
145  int total_bulk_cost;
146  int total_skip_cost;
147  int total_repeat_cost;
148 
149  int temp_cost;
150  int j;
151 
152  uint8_t *this_line = p-> data[0] + line*p-> linesize[0] +
153  (width - 1)*s->pixel_size;
154  uint8_t *prev_line = s->previous_frame.data[0] + line*s->previous_frame.linesize[0] +
155  (width - 1)*s->pixel_size;
156 
157  s->length_table[width] = 0;
158  skipcount = 0;
159 
160  for (i = width - 1; i >= 0; i--) {
161 
162  if (!s->avctx->coded_frame->key_frame && !memcmp(this_line, prev_line, s->pixel_size))
163  skipcount = FFMIN(skipcount + 1, MAX_RLE_SKIP);
164  else
165  skipcount = 0;
166 
167  total_skip_cost = s->length_table[i + skipcount] + 2;
168  s->skip_table[i] = skipcount;
169 
170 
171  if (i < width - 1 && !memcmp(this_line, this_line + s->pixel_size, s->pixel_size))
172  repeatcount = FFMIN(repeatcount + 1, MAX_RLE_REPEAT);
173  else
174  repeatcount = 1;
175 
176  total_repeat_cost = s->length_table[i + repeatcount] + 1 + s->pixel_size;
177 
178  /* skip code is free for the first pixel, it costs one byte for repeat and bulk copy
179  * so let's make it aware */
180  if (i == 0) {
181  total_skip_cost--;
182  total_repeat_cost++;
183  }
184 
185  if (repeatcount > 1 && (skipcount == 0 || total_repeat_cost < total_skip_cost)) {
186  /* repeat is the best */
187  s->length_table[i] = total_repeat_cost;
188  s->rlecode_table[i] = -repeatcount;
189  }
190  else if (skipcount > 0) {
191  /* skip is the best choice here */
192  s->length_table[i] = total_skip_cost;
193  s->rlecode_table[i] = 0;
194  }
195  else {
196  /* We cannot do neither skip nor repeat
197  * thus we search for the best bulk copy to do */
198 
199  int limit = FFMIN(width - i, MAX_RLE_BULK);
200 
201  temp_cost = 1 + s->pixel_size + !i;
202  total_bulk_cost = INT_MAX;
203 
204  for (j = 1; j <= limit; j++) {
205  if (s->length_table[i + j] + temp_cost < total_bulk_cost) {
206  /* We have found a better bulk copy ... */
207  total_bulk_cost = s->length_table[i + j] + temp_cost;
208  bulkcount = j;
209  }
210  temp_cost += s->pixel_size;
211  }
212 
213  s->length_table[i] = total_bulk_cost;
214  s->rlecode_table[i] = bulkcount;
215  }
216 
217  this_line -= s->pixel_size;
218  prev_line -= s->pixel_size;
219  }
220 
221  /* Good ! Now we have the best sequence for this line, let's ouput it */
222 
223  /* We do a special case for the first pixel so that we avoid testing it in
224  * the whole loop */
225 
226  i=0;
227  this_line = p-> data[0] + line*p->linesize[0];
228 
229  if (s->rlecode_table[0] == 0) {
230  bytestream_put_byte(buf, s->skip_table[0] + 1);
231  i += s->skip_table[0];
232  }
233  else bytestream_put_byte(buf, 1);
234 
235 
236  while (i < width) {
237  rlecode = s->rlecode_table[i];
238  bytestream_put_byte(buf, rlecode);
239  if (rlecode == 0) {
240  /* Write a skip sequence */
241  bytestream_put_byte(buf, s->skip_table[i] + 1);
242  i += s->skip_table[i];
243  }
244  else if (rlecode > 0) {
245  /* bulk copy */
246  bytestream_put_buffer(buf, this_line + i*s->pixel_size, rlecode*s->pixel_size);
247  i += rlecode;
248  }
249  else {
250  /* repeat the bits */
251  bytestream_put_buffer(buf, this_line + i*s->pixel_size, s->pixel_size);
252  i -= rlecode;
253  }
254  }
255  bytestream_put_byte(buf, -1); // end RLE line
256 }
257 
259 static int encode_frame(QtrleEncContext *s, const AVFrame *p, uint8_t *buf)
260 {
261  int i;
262  int start_line = 0;
263  int end_line = s->avctx->height;
264  uint8_t *orig_buf = buf;
265 
266  if (!s->avctx->coded_frame->key_frame) {
267  unsigned line_size = s->avctx->width * s->pixel_size;
268  for (start_line = 0; start_line < s->avctx->height; start_line++)
269  if (memcmp(p->data[0] + start_line*p->linesize[0],
270  s->previous_frame.data[0] + start_line*s->previous_frame.linesize[0],
271  line_size))
272  break;
273 
274  for (end_line=s->avctx->height; end_line > start_line; end_line--)
275  if (memcmp(p->data[0] + (end_line - 1)*p->linesize[0],
276  s->previous_frame.data[0] + (end_line - 1)*s->previous_frame.linesize[0],
277  line_size))
278  break;
279  }
280 
281  bytestream_put_be32(&buf, 0); // CHUNK SIZE, patched later
282 
283  if ((start_line == 0 && end_line == s->avctx->height) || start_line == s->avctx->height)
284  bytestream_put_be16(&buf, 0); // header
285  else {
286  bytestream_put_be16(&buf, 8); // header
287  bytestream_put_be16(&buf, start_line); // starting line
288  bytestream_put_be16(&buf, 0); // unknown
289  bytestream_put_be16(&buf, end_line - start_line); // lines to update
290  bytestream_put_be16(&buf, 0); // unknown
291  }
292  for (i = start_line; i < end_line; i++)
293  qtrle_encode_line(s, p, i, &buf);
294 
295  bytestream_put_byte(&buf, 0); // zero skip code = frame finished
296  AV_WB32(orig_buf, buf - orig_buf); // patch the chunk size
297  return buf - orig_buf;
298 }
299 
301  const AVFrame *pict, int *got_packet)
302 {
303  QtrleEncContext * const s = avctx->priv_data;
304  AVFrame * const p = avctx->coded_frame;
305  int ret;
306 
307  if ((ret = ff_alloc_packet(pkt, s->max_buf_size)) < 0) {
308  /* Upper bound check for compressed data */
309  av_log(avctx, AV_LOG_ERROR, "Error getting output packet of size %d.\n", s->max_buf_size);
310  return ret;
311  }
312 
313  if (avctx->gop_size == 0 || (s->avctx->frame_number % avctx->gop_size) == 0) {
314  /* I-Frame */
316  p->key_frame = 1;
317  } else {
318  /* P-Frame */
320  p->key_frame = 0;
321  }
322 
323  pkt->size = encode_frame(s, pict, pkt->data);
324 
325  /* save the current frame */
326  av_picture_copy(&s->previous_frame, (const AVPicture *)pict,
327  avctx->pix_fmt, avctx->width, avctx->height);
328 
329  if (p->key_frame)
330  pkt->flags |= AV_PKT_FLAG_KEY;
331  *got_packet = 1;
332 
333  return 0;
334 }
335 
337  .name = "qtrle",
338  .long_name = NULL_IF_CONFIG_SMALL("QuickTime Animation (RLE) video"),
339  .type = AVMEDIA_TYPE_VIDEO,
340  .id = AV_CODEC_ID_QTRLE,
341  .priv_data_size = sizeof(QtrleEncContext),
343  .encode2 = qtrle_encode_frame,
345  .pix_fmts = (const enum AVPixelFormat[]){
347  },
348 };
int linesize[AV_NUM_DATA_POINTERS]
number of bytes per line
Definition: avcodec.h:3044
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:135
misc image utilities
packed RGB 8:8:8, 24bpp, RGBRGB...
Definition: pixfmt.h:67
AVFrame * coded_frame
the picture in the bitstream
Definition: avcodec.h:2548
int size
Definition: avcodec.h:974
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1270
static int encode_frame(QtrleEncContext *s, const AVFrame *p, uint8_t *buf)
Encode frame including header.
Definition: qtrleenc.c:259
four components are given, that&#39;s all.
Definition: avcodec.h:3042
AVCodec.
Definition: avcodec.h:2812
static av_cold int qtrle_encode_end(AVCodecContext *avctx)
Definition: qtrleenc.c:62
void av_picture_copy(AVPicture *dst, const AVPicture *src, enum AVPixelFormat pix_fmt, int width, int height)
Copy image src to dst.
Definition: avpicture.c:119
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:57
#define AV_WB32(p, d)
Definition: intreadwrite.h:239
uint8_t * data[AV_NUM_DATA_POINTERS]
Definition: avcodec.h:3043
AVCodecContext * avctx
Definition: qtrleenc.c:38
const char data[16]
Definition: mxf.c:70
uint8_t * data
Definition: avcodec.h:973
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
AVPicture previous_frame
Definition: qtrleenc.c:40
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2523
void avpicture_free(AVPicture *picture)
Free a picture previously allocated by avpicture_alloc().
Definition: avpicture.c:114
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1019
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
void av_free(void *ptr)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc(). ...
Definition: mem.c:186
#define AVERROR(e)
Definition: error.h:43
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:69
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:145
#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:300
Definition: graph2dot.c:49
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:169
const char * name
Name of the codec implementation.
Definition: avcodec.h:2819
#define MAX_RLE_SKIP
Maximum RLE code for skip.
Definition: qtrleenc.c:35
packed ARGB 8:8:8:8, 32bpp, ARGBARGB...
Definition: pixfmt.h:95
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:979
static av_cold int qtrle_encode_init(AVCodecContext *avctx)
Definition: qtrleenc.c:75
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:222
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:196
#define FFMIN(a, b)
Definition: common.h:57
int width
picture width / height.
Definition: avcodec.h:1229
#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:1245
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:153
main external API structure.
Definition: avcodec.h:1050
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:490
int avpicture_alloc(AVPicture *picture, enum AVPixelFormat pix_fmt, int width, int height)
Allocate memory for a picture.
Definition: avpicture.c:101
packed RGB 5:5:5, 16bpp, (msb)1A 5R 5G 5B(lsb), big-endian, most significant bit to 0 ...
Definition: pixfmt.h:117
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:141
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:129
int gop_size
the number of pictures in a group of pictures, or 0 for intra_only
Definition: avcodec.h:1255
common internal api header.
static av_cold int init(AVCodecParserContext *s)
Definition: h264_parser.c:499
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:1092
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
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:191
int frame_number
Frame counter, set by libavcodec.
Definition: avcodec.h:1838
AVCodec ff_qtrle_encoder
Definition: qtrleenc.c:336
AVPixelFormat
Pixel format.
Definition: pixfmt.h:63
This structure stores compressed data.
Definition: avcodec.h:950
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:205
Predicted.
Definition: avutil.h:254