fa1209e5c51c3c5cbbe40b9e35e2e53905cee711
[libav.git] / libavcodec / a64multienc.c
1 /*
2 * a64 video encoder - multicolor modes
3 * Copyright (c) 2009 Tobias Bindhammer
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 * a64 video encoder - multicolor modes
25 */
26
27 #include "a64enc.h"
28 #include "a64colors.h"
29 #include "a64tables.h"
30 #include "elbg.h"
31 #include "libavutil/intreadwrite.h"
32
33 #define DITHERSTEPS 8
34 #define CHARSET_CHARS 256
35 #define INTERLACED 1
36 #define CROP_SCREENS 1
37
38 /* gray gradient */
39 static const int mc_colors[5]={0x0,0xb,0xc,0xf,0x1};
40
41 /* other possible gradients - to be tested */
42 //static const int mc_colors[5]={0x0,0x8,0xa,0xf,0x7};
43 //static const int mc_colors[5]={0x0,0x9,0x8,0xa,0x3};
44
45 static void to_meta_with_crop(AVCodecContext *avctx, AVFrame *p, int *dest)
46 {
47 int blockx, blocky, x, y;
48 int luma = 0;
49 int height = FFMIN(avctx->height, C64YRES);
50 int width = FFMIN(avctx->width , C64XRES);
51 uint8_t *src = p->data[0];
52
53 for (blocky = 0; blocky < C64YRES; blocky += 8) {
54 for (blockx = 0; blockx < C64XRES; blockx += 8) {
55 for (y = blocky; y < blocky + 8 && y < C64YRES; y++) {
56 for (x = blockx; x < blockx + 8 && x < C64XRES; x += 2) {
57 if(x < width && y < height) {
58 /* build average over 2 pixels */
59 luma = (src[(x + 0 + y * p->linesize[0])] +
60 src[(x + 1 + y * p->linesize[0])]) / 2;
61 /* write blocks as linear data now so they are suitable for elbg */
62 dest[0] = luma;
63 }
64 dest++;
65 }
66 }
67 }
68 }
69 }
70
71 static void render_charset(AVCodecContext *avctx, uint8_t *charset,
72 uint8_t *colrammap)
73 {
74 A64Context *c = avctx->priv_data;
75 uint8_t row1, row2;
76 int charpos, x, y;
77 int a, b;
78 uint8_t pix;
79 int lowdiff, highdiff;
80 int *best_cb = c->mc_best_cb;
81 static uint8_t index1[256];
82 static uint8_t index2[256];
83 static uint8_t dither[256];
84 int i;
85 int distance;
86
87 /* generate lookup-tables for dither and index before looping */
88 i = 0;
89 for (a=0; a < 256; a++) {
90 if(i < c->mc_pal_size -1 && a == c->mc_luma_vals[i + 1]) {
91 distance = c->mc_luma_vals[i + 1] - c->mc_luma_vals[i];
92 for(b = 0; b <= distance; b++) {
93 dither[c->mc_luma_vals[i] + b] = b * (DITHERSTEPS - 1) / distance;
94 }
95 i++;
96 }
97 if(i >= c->mc_pal_size - 1) dither[a] = 0;
98 index1[a] = i;
99 index2[a] = FFMIN(i + 1, c->mc_pal_size - 1);
100 }
101
102 /* and render charset */
103 for (charpos = 0; charpos < CHARSET_CHARS; charpos++) {
104 lowdiff = 0;
105 highdiff = 0;
106 for (y = 0; y < 8; y++) {
107 row1 = 0; row2 = 0;
108 for (x = 0; x < 4; x++) {
109 pix = best_cb[y * 4 + x];
110
111 /* accumulate error for brightest/darkest color */
112 if (index1[pix] >= 3)
113 highdiff += pix - c->mc_luma_vals[3];
114 if (index1[pix] < 1)
115 lowdiff += c->mc_luma_vals[1] - pix;
116
117 row1 <<= 2;
118
119 if (INTERLACED) {
120 row2 <<= 2;
121 if (interlaced_dither_patterns[dither[pix]][(y & 3) * 2 + 0][x & 3])
122 row1 |= 3-(index2[pix] & 3);
123 else
124 row1 |= 3-(index1[pix] & 3);
125
126 if (interlaced_dither_patterns[dither[pix]][(y & 3) * 2 + 1][x & 3])
127 row2 |= 3-(index2[pix] & 3);
128 else
129 row2 |= 3-(index1[pix] & 3);
130 }
131 else {
132 if (multi_dither_patterns[dither[pix]][(y & 3)][x & 3])
133 row1 |= 3-(index2[pix] & 3);
134 else
135 row1 |= 3-(index1[pix] & 3);
136 }
137 }
138 charset[y+0x000] = row1;
139 if (INTERLACED) charset[y+0x800] = row2;
140 }
141 /* do we need to adjust pixels? */
142 if (highdiff > 0 && lowdiff > 0 && c->mc_use_5col) {
143 if (lowdiff > highdiff) {
144 for (x = 0; x < 32; x++)
145 best_cb[x] = FFMIN(c->mc_luma_vals[3], best_cb[x]);
146 } else {
147 for (x = 0; x < 32; x++)
148 best_cb[x] = FFMAX(c->mc_luma_vals[1], best_cb[x]);
149 }
150 charpos--; /* redo now adjusted char */
151 /* no adjustment needed, all fine */
152 } else {
153 /* advance pointers */
154 best_cb += 32;
155 charset += 8;
156
157 /* remember colorram value */
158 colrammap[charpos] = (highdiff > 0);
159 }
160 }
161 }
162
163 static av_cold int a64multi_close_encoder(AVCodecContext *avctx)
164 {
165 A64Context *c = avctx->priv_data;
166 av_free(c->mc_meta_charset);
167 av_free(c->mc_best_cb);
168 av_free(c->mc_charset);
169 av_free(c->mc_charmap);
170 av_free(c->mc_colram);
171 return 0;
172 }
173
174 static av_cold int a64multi_init_encoder(AVCodecContext *avctx)
175 {
176 A64Context *c = avctx->priv_data;
177 int a;
178 av_lfg_init(&c->randctx, 1);
179
180 if (avctx->global_quality < 1) {
181 c->mc_lifetime = 4;
182 } else {
183 c->mc_lifetime = avctx->global_quality /= FF_QP2LAMBDA;
184 }
185
186 av_log(avctx, AV_LOG_INFO, "charset lifetime set to %d frame(s)\n", c->mc_lifetime);
187
188 c->mc_frame_counter = 0;
189 c->mc_use_5col = avctx->codec->id == CODEC_ID_A64_MULTI5;
190 c->mc_pal_size = 4 + c->mc_use_5col;
191
192 /* precalc luma values for later use */
193 for (a = 0; a < c->mc_pal_size; a++) {
194 c->mc_luma_vals[a]=a64_palette[mc_colors[a]][0] * 0.30 +
195 a64_palette[mc_colors[a]][1] * 0.59 +
196 a64_palette[mc_colors[a]][2] * 0.11;
197 }
198
199 if (!(c->mc_meta_charset = av_malloc(32000 * c->mc_lifetime * sizeof(int))) ||
200 !(c->mc_best_cb = av_malloc(CHARSET_CHARS * 32 * sizeof(int))) ||
201 !(c->mc_charmap = av_mallocz(1000 * c->mc_lifetime * sizeof(int))) ||
202 !(c->mc_colram = av_mallocz(CHARSET_CHARS * sizeof(uint8_t))) ||
203 !(c->mc_charset = av_malloc(0x800 * (INTERLACED+1) * sizeof(uint8_t)))) {
204 av_log(avctx, AV_LOG_ERROR, "Failed to allocate buffer memory.\n");
205 return AVERROR(ENOMEM);
206 }
207
208 /* set up extradata */
209 if (!(avctx->extradata = av_mallocz(8 * 4 + FF_INPUT_BUFFER_PADDING_SIZE))) {
210 av_log(avctx, AV_LOG_ERROR, "Failed to allocate memory for extradata.\n");
211 return AVERROR(ENOMEM);
212 }
213 avctx->extradata_size = 8 * 4;
214 AV_WB32(avctx->extradata, c->mc_lifetime);
215 AV_WB32(avctx->extradata + 16, INTERLACED);
216
217 avcodec_get_frame_defaults(&c->picture);
218 avctx->coded_frame = &c->picture;
219 avctx->coded_frame->pict_type = FF_I_TYPE;
220 avctx->coded_frame->key_frame = 1;
221 if (!avctx->codec_tag)
222 avctx->codec_tag = AV_RL32("a64m");
223
224 return 0;
225 }
226
227 static void a64_compress_colram(unsigned char *buf, int *charmap, uint8_t *colram)
228 {
229 int a;
230 uint8_t temp;
231 /* only needs to be done in 5col mode */
232 /* XXX could be squeezed to 0x80 bytes */
233 for (a = 0; a < 256; a++) {
234 temp = colram[charmap[a + 0x000]] << 0;
235 temp |= colram[charmap[a + 0x100]] << 1;
236 temp |= colram[charmap[a + 0x200]] << 2;
237 if (a < 0xe8) temp |= colram[charmap[a + 0x300]] << 3;
238 buf[a] = temp << 2;
239 }
240 }
241
242 static int a64multi_encode_frame(AVCodecContext *avctx, unsigned char *buf,
243 int buf_size, void *data)
244 {
245 A64Context *c = avctx->priv_data;
246 AVFrame *pict = data;
247 AVFrame *const p = (AVFrame *) & c->picture;
248
249 int frame;
250 int x, y;
251 int b_height;
252 int b_width;
253
254 int req_size;
255 int num_frames = c->mc_lifetime;
256
257 int *charmap = c->mc_charmap;
258 uint8_t *colram = c->mc_colram;
259 uint8_t *charset = c->mc_charset;
260 int *meta = c->mc_meta_charset;
261 int *best_cb = c->mc_best_cb;
262
263 int charset_size = 0x800 * (INTERLACED + 1);
264 int colram_size = 0x100 * c->mc_use_5col;
265 int screen_size;
266
267 if(CROP_SCREENS) {
268 b_height = FFMIN(avctx->height,C64YRES) >> 3;
269 b_width = FFMIN(avctx->width ,C64XRES) >> 3;
270 screen_size = b_width * b_height;
271 } else {
272 b_height = C64YRES >> 3;
273 b_width = C64XRES >> 3;
274 screen_size = 0x400;
275 }
276
277 /* no data, means end encoding asap */
278 if (!data) {
279 /* all done, end encoding */
280 if (!c->mc_lifetime) return 0;
281 /* no more frames in queue, prepare to flush remaining frames */
282 if (!c->mc_frame_counter) {
283 num_frames = c->mc_lifetime;
284 c->mc_lifetime = 0;
285 }
286 /* still frames in queue so limit lifetime to remaining frames */
287 else c->mc_lifetime = c->mc_frame_counter;
288 /* still new data available */
289 } else {
290 /* fill up mc_meta_charset with data until lifetime exceeds */
291 if (c->mc_frame_counter < c->mc_lifetime) {
292 *p = *pict;
293 p->pict_type = FF_I_TYPE;
294 p->key_frame = 1;
295 to_meta_with_crop(avctx, p, meta + 32000 * c->mc_frame_counter);
296 c->mc_frame_counter++;
297 /* lifetime is not reached so wait for next frame first */
298 return 0;
299 }
300 }
301
302 /* lifetime reached so now convert X frames at once */
303 if (c->mc_frame_counter == c->mc_lifetime) {
304 req_size = 0;
305 /* any frames to encode? */
306 if (c->mc_lifetime) {
307 /* calc optimal new charset + charmaps */
308 ff_init_elbg(meta, 32, 1000 * c->mc_lifetime, best_cb, CHARSET_CHARS, 50, charmap, &c->randctx);
309 ff_do_elbg (meta, 32, 1000 * c->mc_lifetime, best_cb, CHARSET_CHARS, 50, charmap, &c->randctx);
310
311 /* create colorram map and a c64 readable charset */
312 render_charset(avctx, charset, colram);
313
314 /* copy charset to buf */
315 memcpy(buf,charset, charset_size);
316
317 /* advance pointers */
318 buf += charset_size;
319 charset += charset_size;
320 req_size += charset_size;
321 }
322 /* no charset so clean buf */
323 else memset(buf, 0, charset_size);
324
325 /* write x frames to buf */
326 for (frame = 0; frame < c->mc_lifetime; frame++) {
327 /* copy charmap to buf. buf is uchar*, charmap is int*, so no memcpy here, sorry */
328 for (y = 0; y < b_height; y++) {
329 for (x = 0; x < b_width; x++) {
330 buf[y * b_width + x] = charmap[y * b_width + x];
331 }
332 }
333 /* advance pointers */
334 buf += screen_size;
335 req_size += screen_size;
336
337 /* compress and copy colram to buf */
338 if (c->mc_use_5col) {
339 a64_compress_colram(buf, charmap, colram);
340 /* advance pointers */
341 buf += colram_size;
342 req_size += colram_size;
343 }
344
345 /* advance to next charmap */
346 charmap += 1000;
347 }
348
349 AV_WB32(avctx->extradata + 4, c->mc_frame_counter);
350 AV_WB32(avctx->extradata + 8, charset_size);
351 AV_WB32(avctx->extradata + 12, screen_size + colram_size);
352
353 /* reset counter */
354 c->mc_frame_counter = 0;
355
356 if (req_size > buf_size) {
357 av_log(avctx, AV_LOG_ERROR, "buf size too small (need %d, got %d)\n", req_size, buf_size);
358 return -1;
359 }
360 return req_size;
361 }
362 return 0;
363 }
364
365 AVCodec a64multi_encoder = {
366 .name = "a64multi",
367 .type = AVMEDIA_TYPE_VIDEO,
368 .id = CODEC_ID_A64_MULTI,
369 .priv_data_size = sizeof(A64Context),
370 .init = a64multi_init_encoder,
371 .encode = a64multi_encode_frame,
372 .close = a64multi_close_encoder,
373 .pix_fmts = (const enum PixelFormat[]) {PIX_FMT_GRAY8, PIX_FMT_NONE},
374 .long_name = NULL_IF_CONFIG_SMALL("Multicolor charset for Commodore 64"),
375 .capabilities = CODEC_CAP_DELAY,
376 };
377
378 AVCodec a64multi5_encoder = {
379 .name = "a64multi5",
380 .type = AVMEDIA_TYPE_VIDEO,
381 .id = CODEC_ID_A64_MULTI5,
382 .priv_data_size = sizeof(A64Context),
383 .init = a64multi_init_encoder,
384 .encode = a64multi_encode_frame,
385 .close = a64multi_close_encoder,
386 .pix_fmts = (const enum PixelFormat[]) {PIX_FMT_GRAY8, PIX_FMT_NONE},
387 .long_name = NULL_IF_CONFIG_SMALL("Multicolor charset for Commodore 64, extended with 5th color (colram)"),
388 .capabilities = CODEC_CAP_DELAY,
389 };