2 * Quicktime Animation (RLE) Video Encoder
3 * Copyright (C) 2007 Clemens Fruhwirth
4 * Copyright (C) 2007 Alexis Ballier
6 * This file is based on flashsvenc.c.
8 * This file is part of FFmpeg.
10 * FFmpeg 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.
15 * FFmpeg 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.
20 * You should have received a copy of the GNU Lesser General Public
21 * License along with FFmpeg; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25 #include "libavutil/imgutils.h"
27 #include "bytestream.h"
30 /** Maximum RLE code for bulk copy */
31 #define MAX_RLE_BULK 127
32 /** Maximum RLE code for repeat */
33 #define MAX_RLE_REPEAT 128
34 /** Maximum RLE code for skip */
35 #define MAX_RLE_SKIP 254
37 typedef struct QtrleEncContext
{
38 AVCodecContext
*avctx
;
40 AVPicture previous_frame
;
41 unsigned int max_buf_size
;
44 * This array will contain at ith position the value of the best RLE code
45 * if the line started at pixel i
46 * There can be 3 values :
47 * skip (0) : skip as much as possible pixels because they are equal to the
49 * repeat (<-1) : repeat that pixel -rle_code times, still as much as
51 * copy (>0) : copy the raw next rle_code pixels */
52 signed char *rlecode_table
;
54 * This array will contain the length of the best rle encoding of the line
55 * starting at ith pixel */
58 * Will contain at ith position the number of consecutive pixels equal to the previous
59 * frame starting from pixel i */
63 static av_cold
int qtrle_encode_end(AVCodecContext
*avctx
)
65 QtrleEncContext
*s
= avctx
->priv_data
;
67 av_frame_free(&avctx
->coded_frame
);
69 avpicture_free(&s
->previous_frame
);
70 av_free(s
->rlecode_table
);
71 av_free(s
->length_table
);
72 av_free(s
->skip_table
);
76 static av_cold
int qtrle_encode_init(AVCodecContext
*avctx
)
78 QtrleEncContext
*s
= avctx
->priv_data
;
81 if (av_image_check_size(avctx
->width
, avctx
->height
, 0, avctx
) < 0) {
82 return AVERROR(EINVAL
);
85 s
->logical_width
=avctx
->width
;
87 switch (avctx
->pix_fmt
) {
88 case AV_PIX_FMT_GRAY8
:
89 if (avctx
->width
% 4) {
90 av_log(avctx
, AV_LOG_ERROR
, "Width not being a multiple of 4 is not supported\n");
91 return AVERROR(EINVAL
);
93 s
->logical_width
= avctx
->width
/ 4;
96 case AV_PIX_FMT_RGB555BE
:
99 case AV_PIX_FMT_RGB24
:
102 case AV_PIX_FMT_ARGB
:
106 av_log(avctx
, AV_LOG_ERROR
, "Unsupported colorspace.\n");
109 avctx
->bits_per_coded_sample
= avctx
->pix_fmt
== AV_PIX_FMT_GRAY8
? 40 : s
->pixel_size
*8;
111 s
->rlecode_table
= av_mallocz(s
->logical_width
);
112 s
->skip_table
= av_mallocz(s
->logical_width
);
113 s
->length_table
= av_mallocz_array(s
->logical_width
+ 1, sizeof(int));
114 if (!s
->skip_table
|| !s
->length_table
|| !s
->rlecode_table
) {
115 av_log(avctx
, AV_LOG_ERROR
, "Error allocating memory.\n");
116 return AVERROR(ENOMEM
);
118 if ((ret
= avpicture_alloc(&s
->previous_frame
, avctx
->pix_fmt
, avctx
->width
, avctx
->height
)) < 0) {
119 av_log(avctx
, AV_LOG_ERROR
, "Error allocating picture\n");
123 s
->max_buf_size
= s
->logical_width
*s
->avctx
->height
*s
->pixel_size
*2 /* image base material */
124 + 15 /* header + footer */
125 + s
->avctx
->height
*2 /* skip code+rle end */
126 + s
->logical_width
/MAX_RLE_BULK
+ 1 /* rle codes */;
128 avctx
->coded_frame
= av_frame_alloc();
129 if (!avctx
->coded_frame
) {
130 qtrle_encode_end(avctx
);
131 return AVERROR(ENOMEM
);
138 * Compute the best RLE sequence for a line
140 static void qtrle_encode_line(QtrleEncContext
*s
, const AVFrame
*p
, int line
, uint8_t **buf
)
142 int width
=s
->logical_width
;
146 /* This will be the number of pixels equal to the preivous frame one's
147 * starting from the ith pixel */
148 unsigned int skipcount
;
149 /* This will be the number of consecutive equal pixels in the current
150 * frame, starting from the ith one also */
151 unsigned int av_uninit(repeatcount
);
153 /* The cost of the three different possibilities */
155 int total_repeat_cost
;
158 int lowest_bulk_cost
;
159 int lowest_bulk_cost_index
;
160 int sec_lowest_bulk_cost
;
161 int sec_lowest_bulk_cost_index
;
163 uint8_t *this_line
= p
-> data
[0] + line
*p
-> linesize
[0] +
164 (width
- 1)*s
->pixel_size
;
165 uint8_t *prev_line
= s
->previous_frame
.data
[0] + line
*s
->previous_frame
.linesize
[0] +
166 (width
- 1)*s
->pixel_size
;
168 s
->length_table
[width
] = 0;
172 lowest_bulk_cost
= INT_MAX
/ 2;
173 lowest_bulk_cost_index
= width
;
174 sec_lowest_bulk_cost
= INT_MAX
/ 2;
175 sec_lowest_bulk_cost_index
= width
;
177 base_bulk_cost
= 1 + s
->pixel_size
;
179 for (i
= width
- 1; i
>= 0; i
--) {
183 /* If our lowest bulk cost index is too far away, replace it
184 * with the next lowest bulk cost */
185 if (FFMIN(width
, i
+ MAX_RLE_BULK
) < lowest_bulk_cost_index
) {
186 lowest_bulk_cost
= sec_lowest_bulk_cost
;
187 lowest_bulk_cost_index
= sec_lowest_bulk_cost_index
;
189 sec_lowest_bulk_cost
= INT_MAX
/ 2;
190 sec_lowest_bulk_cost_index
= width
;
193 /* Deal with the first pixel's bulk cost */
197 sec_lowest_bulk_cost
++;
200 /* Look at the bulk cost of the previous loop and see if it is
201 * a new lower bulk cost */
202 prev_bulk_cost
= s
->length_table
[i
+ 1] + base_bulk_cost
;
203 if (prev_bulk_cost
<= sec_lowest_bulk_cost
) {
204 /* If it's lower than the 2nd lowest, then it may be lower
206 if (prev_bulk_cost
<= lowest_bulk_cost
) {
208 /* If we have found a new lowest bulk cost,
209 * then the 2nd lowest bulk cost is now farther than the
210 * lowest bulk cost, and will never be used */
211 sec_lowest_bulk_cost
= INT_MAX
/ 2;
213 lowest_bulk_cost
= prev_bulk_cost
;
214 lowest_bulk_cost_index
= i
+ 1;
216 /* Then it must be the 2nd lowest bulk cost */
217 sec_lowest_bulk_cost
= prev_bulk_cost
;
218 sec_lowest_bulk_cost_index
= i
+ 1;
222 if (!s
->avctx
->coded_frame
->key_frame
&& !memcmp(this_line
, prev_line
, s
->pixel_size
))
223 skipcount
= FFMIN(skipcount
+ 1, MAX_RLE_SKIP
);
227 total_skip_cost
= s
->length_table
[i
+ skipcount
] + 2;
228 s
->skip_table
[i
] = skipcount
;
231 if (i
< width
- 1 && !memcmp(this_line
, this_line
+ s
->pixel_size
, s
->pixel_size
))
232 repeatcount
= FFMIN(repeatcount
+ 1, MAX_RLE_REPEAT
);
236 total_repeat_cost
= s
->length_table
[i
+ repeatcount
] + 1 + s
->pixel_size
;
238 /* skip code is free for the first pixel, it costs one byte for repeat and bulk copy
239 * so let's make it aware */
245 if (repeatcount
> 1 && (skipcount
== 0 || total_repeat_cost
< total_skip_cost
)) {
246 /* repeat is the best */
247 s
->length_table
[i
] = total_repeat_cost
;
248 s
->rlecode_table
[i
] = -repeatcount
;
250 else if (skipcount
> 0) {
251 /* skip is the best choice here */
252 s
->length_table
[i
] = total_skip_cost
;
253 s
->rlecode_table
[i
] = 0;
256 /* We cannot do neither skip nor repeat
257 * thus we use the best bulk copy */
259 s
->length_table
[i
] = lowest_bulk_cost
;
260 s
->rlecode_table
[i
] = lowest_bulk_cost_index
- i
;
264 /* These bulk costs increase every iteration */
265 lowest_bulk_cost
+= s
->pixel_size
;
266 sec_lowest_bulk_cost
+= s
->pixel_size
;
268 this_line
-= s
->pixel_size
;
269 prev_line
-= s
->pixel_size
;
272 /* Good ! Now we have the best sequence for this line, let's output it */
274 /* We do a special case for the first pixel so that we avoid testing it in
278 this_line
= p
-> data
[0] + line
*p
->linesize
[0];
280 if (s
->rlecode_table
[0] == 0) {
281 bytestream_put_byte(buf
, s
->skip_table
[0] + 1);
282 i
+= s
->skip_table
[0];
284 else bytestream_put_byte(buf
, 1);
288 rlecode
= s
->rlecode_table
[i
];
289 bytestream_put_byte(buf
, rlecode
);
291 /* Write a skip sequence */
292 bytestream_put_byte(buf
, s
->skip_table
[i
] + 1);
293 i
+= s
->skip_table
[i
];
295 else if (rlecode
> 0) {
297 if (s
->avctx
->pix_fmt
== AV_PIX_FMT_GRAY8
) {
299 // QT grayscale colorspace has 0=white and 255=black, we will
300 // ignore the palette that is included in the AVFrame because
301 // AV_PIX_FMT_GRAY8 has defined color mapping
302 for (j
= 0; j
< rlecode
*s
->pixel_size
; ++j
)
303 bytestream_put_byte(buf
, *(this_line
+ i
*s
->pixel_size
+ j
) ^ 0xff);
305 bytestream_put_buffer(buf
, this_line
+ i
*s
->pixel_size
, rlecode
*s
->pixel_size
);
310 /* repeat the bits */
311 if (s
->avctx
->pix_fmt
== AV_PIX_FMT_GRAY8
) {
313 // QT grayscale colorspace has 0=white and 255=black, ...
314 for (j
= 0; j
< s
->pixel_size
; ++j
)
315 bytestream_put_byte(buf
, *(this_line
+ i
*s
->pixel_size
+ j
) ^ 0xff);
317 bytestream_put_buffer(buf
, this_line
+ i
*s
->pixel_size
, s
->pixel_size
);
322 bytestream_put_byte(buf
, -1); // end RLE line
325 /** Encode frame including header */
326 static int encode_frame(QtrleEncContext
*s
, const AVFrame
*p
, uint8_t *buf
)
330 int end_line
= s
->avctx
->height
;
331 uint8_t *orig_buf
= buf
;
333 if (!s
->avctx
->coded_frame
->key_frame
) {
334 unsigned line_size
= s
->logical_width
* s
->pixel_size
;
335 for (start_line
= 0; start_line
< s
->avctx
->height
; start_line
++)
336 if (memcmp(p
->data
[0] + start_line
*p
->linesize
[0],
337 s
->previous_frame
.data
[0] + start_line
*s
->previous_frame
.linesize
[0],
341 for (end_line
=s
->avctx
->height
; end_line
> start_line
; end_line
--)
342 if (memcmp(p
->data
[0] + (end_line
- 1)*p
->linesize
[0],
343 s
->previous_frame
.data
[0] + (end_line
- 1)*s
->previous_frame
.linesize
[0],
348 bytestream_put_be32(&buf
, 0); // CHUNK SIZE, patched later
350 if ((start_line
== 0 && end_line
== s
->avctx
->height
) || start_line
== s
->avctx
->height
)
351 bytestream_put_be16(&buf
, 0); // header
353 bytestream_put_be16(&buf
, 8); // header
354 bytestream_put_be16(&buf
, start_line
); // starting line
355 bytestream_put_be16(&buf
, 0); // unknown
356 bytestream_put_be16(&buf
, end_line
- start_line
); // lines to update
357 bytestream_put_be16(&buf
, 0); // unknown
359 for (i
= start_line
; i
< end_line
; i
++)
360 qtrle_encode_line(s
, p
, i
, &buf
);
362 bytestream_put_byte(&buf
, 0); // zero skip code = frame finished
363 AV_WB32(orig_buf
, buf
- orig_buf
); // patch the chunk size
364 return buf
- orig_buf
;
367 static int qtrle_encode_frame(AVCodecContext
*avctx
, AVPacket
*pkt
,
368 const AVFrame
*pict
, int *got_packet
)
370 QtrleEncContext
* const s
= avctx
->priv_data
;
371 AVFrame
* const p
= avctx
->coded_frame
;
374 if ((ret
= ff_alloc_packet2(avctx
, pkt
, s
->max_buf_size
)) < 0)
377 if (avctx
->gop_size
== 0 || (s
->avctx
->frame_number
% avctx
->gop_size
) == 0) {
379 p
->pict_type
= AV_PICTURE_TYPE_I
;
383 p
->pict_type
= AV_PICTURE_TYPE_P
;
387 pkt
->size
= encode_frame(s
, pict
, pkt
->data
);
389 /* save the current frame */
390 av_picture_copy(&s
->previous_frame
, (const AVPicture
*)pict
,
391 avctx
->pix_fmt
, avctx
->width
, avctx
->height
);
394 pkt
->flags
|= AV_PKT_FLAG_KEY
;
400 AVCodec ff_qtrle_encoder
= {
402 .long_name
= NULL_IF_CONFIG_SMALL("QuickTime Animation (RLE) video"),
403 .type
= AVMEDIA_TYPE_VIDEO
,
404 .id
= AV_CODEC_ID_QTRLE
,
405 .priv_data_size
= sizeof(QtrleEncContext
),
406 .init
= qtrle_encode_init
,
407 .encode2
= qtrle_encode_frame
,
408 .close
= qtrle_encode_end
,
409 .pix_fmts
= (const enum AVPixelFormat
[]){
410 AV_PIX_FMT_RGB24
, AV_PIX_FMT_RGB555BE
, AV_PIX_FMT_ARGB
, AV_PIX_FMT_GRAY8
, AV_PIX_FMT_NONE