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2ba45a60 DM |
1 | /* |
2 | * PNG image format | |
3 | * Copyright (c) 2003 Fabrice Bellard | |
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 | #include "avcodec.h" | |
23 | #include "internal.h" | |
24 | #include "bytestream.h" | |
25 | #include "huffyuvencdsp.h" | |
26 | #include "png.h" | |
27 | ||
28 | #include "libavutil/avassert.h" | |
29 | #include "libavutil/opt.h" | |
30 | ||
31 | #include <zlib.h> | |
32 | ||
33 | #define IOBUF_SIZE 4096 | |
34 | ||
35 | typedef struct PNGEncContext { | |
36 | AVClass *class; | |
37 | HuffYUVEncDSPContext hdsp; | |
38 | ||
39 | uint8_t *bytestream; | |
40 | uint8_t *bytestream_start; | |
41 | uint8_t *bytestream_end; | |
42 | ||
43 | int filter_type; | |
44 | ||
45 | z_stream zstream; | |
46 | uint8_t buf[IOBUF_SIZE]; | |
47 | int dpi; ///< Physical pixel density, in dots per inch, if set | |
48 | int dpm; ///< Physical pixel density, in dots per meter, if set | |
49 | } PNGEncContext; | |
50 | ||
51 | static void png_get_interlaced_row(uint8_t *dst, int row_size, | |
52 | int bits_per_pixel, int pass, | |
53 | const uint8_t *src, int width) | |
54 | { | |
55 | int x, mask, dst_x, j, b, bpp; | |
56 | uint8_t *d; | |
57 | const uint8_t *s; | |
58 | static const int masks[] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff}; | |
59 | ||
60 | mask = masks[pass]; | |
61 | switch (bits_per_pixel) { | |
62 | case 1: | |
63 | memset(dst, 0, row_size); | |
64 | dst_x = 0; | |
65 | for (x = 0; x < width; x++) { | |
66 | j = (x & 7); | |
67 | if ((mask << j) & 0x80) { | |
68 | b = (src[x >> 3] >> (7 - j)) & 1; | |
69 | dst[dst_x >> 3] |= b << (7 - (dst_x & 7)); | |
70 | dst_x++; | |
71 | } | |
72 | } | |
73 | break; | |
74 | default: | |
75 | bpp = bits_per_pixel >> 3; | |
76 | d = dst; | |
77 | s = src; | |
78 | for (x = 0; x < width; x++) { | |
79 | j = x & 7; | |
80 | if ((mask << j) & 0x80) { | |
81 | memcpy(d, s, bpp); | |
82 | d += bpp; | |
83 | } | |
84 | s += bpp; | |
85 | } | |
86 | break; | |
87 | } | |
88 | } | |
89 | ||
90 | static void sub_png_paeth_prediction(uint8_t *dst, uint8_t *src, uint8_t *top, | |
91 | int w, int bpp) | |
92 | { | |
93 | int i; | |
94 | for (i = 0; i < w; i++) { | |
95 | int a, b, c, p, pa, pb, pc; | |
96 | ||
97 | a = src[i - bpp]; | |
98 | b = top[i]; | |
99 | c = top[i - bpp]; | |
100 | ||
101 | p = b - c; | |
102 | pc = a - c; | |
103 | ||
104 | pa = abs(p); | |
105 | pb = abs(pc); | |
106 | pc = abs(p + pc); | |
107 | ||
108 | if (pa <= pb && pa <= pc) | |
109 | p = a; | |
110 | else if (pb <= pc) | |
111 | p = b; | |
112 | else | |
113 | p = c; | |
114 | dst[i] = src[i] - p; | |
115 | } | |
116 | } | |
117 | ||
118 | static void sub_left_prediction(PNGEncContext *c, uint8_t *dst, const uint8_t *src, int bpp, int size) | |
119 | { | |
120 | const uint8_t *src1 = src + bpp; | |
121 | const uint8_t *src2 = src; | |
122 | int x, unaligned_w; | |
123 | ||
124 | memcpy(dst, src, bpp); | |
125 | dst += bpp; | |
126 | size -= bpp; | |
127 | unaligned_w = FFMIN(32 - bpp, size); | |
128 | for (x = 0; x < unaligned_w; x++) | |
129 | *dst++ = *src1++ - *src2++; | |
130 | size -= unaligned_w; | |
131 | c->hdsp.diff_bytes(dst, src1, src2, size); | |
132 | } | |
133 | ||
134 | static void png_filter_row(PNGEncContext *c, uint8_t *dst, int filter_type, | |
135 | uint8_t *src, uint8_t *top, int size, int bpp) | |
136 | { | |
137 | int i; | |
138 | ||
139 | switch (filter_type) { | |
140 | case PNG_FILTER_VALUE_NONE: | |
141 | memcpy(dst, src, size); | |
142 | break; | |
143 | case PNG_FILTER_VALUE_SUB: | |
144 | sub_left_prediction(c, dst, src, bpp, size); | |
145 | break; | |
146 | case PNG_FILTER_VALUE_UP: | |
147 | c->hdsp.diff_bytes(dst, src, top, size); | |
148 | break; | |
149 | case PNG_FILTER_VALUE_AVG: | |
150 | for (i = 0; i < bpp; i++) | |
151 | dst[i] = src[i] - (top[i] >> 1); | |
152 | for (; i < size; i++) | |
153 | dst[i] = src[i] - ((src[i - bpp] + top[i]) >> 1); | |
154 | break; | |
155 | case PNG_FILTER_VALUE_PAETH: | |
156 | for (i = 0; i < bpp; i++) | |
157 | dst[i] = src[i] - top[i]; | |
158 | sub_png_paeth_prediction(dst + i, src + i, top + i, size - i, bpp); | |
159 | break; | |
160 | } | |
161 | } | |
162 | ||
163 | static uint8_t *png_choose_filter(PNGEncContext *s, uint8_t *dst, | |
164 | uint8_t *src, uint8_t *top, int size, int bpp) | |
165 | { | |
166 | int pred = s->filter_type; | |
167 | av_assert0(bpp || !pred); | |
168 | if (!top && pred) | |
169 | pred = PNG_FILTER_VALUE_SUB; | |
170 | if (pred == PNG_FILTER_VALUE_MIXED) { | |
171 | int i; | |
172 | int cost, bcost = INT_MAX; | |
173 | uint8_t *buf1 = dst, *buf2 = dst + size + 16; | |
174 | for (pred = 0; pred < 5; pred++) { | |
175 | png_filter_row(s, buf1 + 1, pred, src, top, size, bpp); | |
176 | buf1[0] = pred; | |
177 | cost = 0; | |
178 | for (i = 0; i <= size; i++) | |
179 | cost += abs((int8_t) buf1[i]); | |
180 | if (cost < bcost) { | |
181 | bcost = cost; | |
182 | FFSWAP(uint8_t *, buf1, buf2); | |
183 | } | |
184 | } | |
185 | return buf2; | |
186 | } else { | |
187 | png_filter_row(s, dst + 1, pred, src, top, size, bpp); | |
188 | dst[0] = pred; | |
189 | return dst; | |
190 | } | |
191 | } | |
192 | ||
193 | static void png_write_chunk(uint8_t **f, uint32_t tag, | |
194 | const uint8_t *buf, int length) | |
195 | { | |
196 | uint32_t crc; | |
197 | uint8_t tagbuf[4]; | |
198 | ||
199 | bytestream_put_be32(f, length); | |
200 | crc = crc32(0, Z_NULL, 0); | |
201 | AV_WL32(tagbuf, tag); | |
202 | crc = crc32(crc, tagbuf, 4); | |
203 | bytestream_put_be32(f, av_bswap32(tag)); | |
204 | if (length > 0) { | |
205 | crc = crc32(crc, buf, length); | |
206 | memcpy(*f, buf, length); | |
207 | *f += length; | |
208 | } | |
209 | bytestream_put_be32(f, crc); | |
210 | } | |
211 | ||
212 | /* XXX: do filtering */ | |
213 | static int png_write_row(PNGEncContext *s, const uint8_t *data, int size) | |
214 | { | |
215 | int ret; | |
216 | ||
217 | s->zstream.avail_in = size; | |
218 | s->zstream.next_in = data; | |
219 | while (s->zstream.avail_in > 0) { | |
220 | ret = deflate(&s->zstream, Z_NO_FLUSH); | |
221 | if (ret != Z_OK) | |
222 | return -1; | |
223 | if (s->zstream.avail_out == 0) { | |
224 | if (s->bytestream_end - s->bytestream > IOBUF_SIZE + 100) | |
225 | png_write_chunk(&s->bytestream, | |
226 | MKTAG('I', 'D', 'A', 'T'), s->buf, IOBUF_SIZE); | |
227 | s->zstream.avail_out = IOBUF_SIZE; | |
228 | s->zstream.next_out = s->buf; | |
229 | } | |
230 | } | |
231 | return 0; | |
232 | } | |
233 | ||
234 | static int encode_frame(AVCodecContext *avctx, AVPacket *pkt, | |
235 | const AVFrame *pict, int *got_packet) | |
236 | { | |
237 | PNGEncContext *s = avctx->priv_data; | |
238 | const AVFrame *const p = pict; | |
239 | int bit_depth, color_type, y, len, row_size, ret, is_progressive; | |
240 | int bits_per_pixel, pass_row_size, enc_row_size; | |
241 | int64_t max_packet_size; | |
242 | int compression_level; | |
243 | uint8_t *ptr, *top, *crow_buf, *crow; | |
244 | uint8_t *crow_base = NULL; | |
245 | uint8_t *progressive_buf = NULL; | |
246 | uint8_t *top_buf = NULL; | |
247 | ||
248 | is_progressive = !!(avctx->flags & CODEC_FLAG_INTERLACED_DCT); | |
249 | switch (avctx->pix_fmt) { | |
250 | case AV_PIX_FMT_RGBA64BE: | |
251 | bit_depth = 16; | |
252 | color_type = PNG_COLOR_TYPE_RGB_ALPHA; | |
253 | break; | |
254 | case AV_PIX_FMT_RGB48BE: | |
255 | bit_depth = 16; | |
256 | color_type = PNG_COLOR_TYPE_RGB; | |
257 | break; | |
258 | case AV_PIX_FMT_RGBA: | |
259 | bit_depth = 8; | |
260 | color_type = PNG_COLOR_TYPE_RGB_ALPHA; | |
261 | break; | |
262 | case AV_PIX_FMT_RGB24: | |
263 | bit_depth = 8; | |
264 | color_type = PNG_COLOR_TYPE_RGB; | |
265 | break; | |
266 | case AV_PIX_FMT_GRAY16BE: | |
267 | bit_depth = 16; | |
268 | color_type = PNG_COLOR_TYPE_GRAY; | |
269 | break; | |
270 | case AV_PIX_FMT_GRAY8: | |
271 | bit_depth = 8; | |
272 | color_type = PNG_COLOR_TYPE_GRAY; | |
273 | break; | |
274 | case AV_PIX_FMT_GRAY8A: | |
275 | bit_depth = 8; | |
276 | color_type = PNG_COLOR_TYPE_GRAY_ALPHA; | |
277 | break; | |
278 | case AV_PIX_FMT_MONOBLACK: | |
279 | bit_depth = 1; | |
280 | color_type = PNG_COLOR_TYPE_GRAY; | |
281 | break; | |
282 | case AV_PIX_FMT_PAL8: | |
283 | bit_depth = 8; | |
284 | color_type = PNG_COLOR_TYPE_PALETTE; | |
285 | break; | |
286 | default: | |
287 | return -1; | |
288 | } | |
289 | bits_per_pixel = ff_png_get_nb_channels(color_type) * bit_depth; | |
290 | row_size = (avctx->width * bits_per_pixel + 7) >> 3; | |
291 | ||
292 | s->zstream.zalloc = ff_png_zalloc; | |
293 | s->zstream.zfree = ff_png_zfree; | |
294 | s->zstream.opaque = NULL; | |
295 | compression_level = avctx->compression_level == FF_COMPRESSION_DEFAULT | |
296 | ? Z_DEFAULT_COMPRESSION | |
297 | : av_clip(avctx->compression_level, 0, 9); | |
298 | ret = deflateInit2(&s->zstream, compression_level, | |
299 | Z_DEFLATED, 15, 8, Z_DEFAULT_STRATEGY); | |
300 | if (ret != Z_OK) | |
301 | return -1; | |
302 | ||
303 | enc_row_size = deflateBound(&s->zstream, row_size); | |
304 | max_packet_size = avctx->height * (int64_t)(enc_row_size + | |
305 | ((enc_row_size + IOBUF_SIZE - 1) / IOBUF_SIZE) * 12) | |
306 | + FF_MIN_BUFFER_SIZE; | |
307 | if (max_packet_size > INT_MAX) | |
308 | return AVERROR(ENOMEM); | |
309 | if ((ret = ff_alloc_packet2(avctx, pkt, max_packet_size)) < 0) | |
310 | return ret; | |
311 | ||
312 | s->bytestream_start = | |
313 | s->bytestream = pkt->data; | |
314 | s->bytestream_end = pkt->data + pkt->size; | |
315 | ||
316 | crow_base = av_malloc((row_size + 32) << (s->filter_type == PNG_FILTER_VALUE_MIXED)); | |
317 | if (!crow_base) | |
318 | goto fail; | |
319 | // pixel data should be aligned, but there's a control byte before it | |
320 | crow_buf = crow_base + 15; | |
321 | if (is_progressive) { | |
322 | progressive_buf = av_malloc(row_size + 1); | |
323 | if (!progressive_buf) | |
324 | goto fail; | |
325 | } | |
326 | if (is_progressive) { | |
327 | top_buf = av_malloc(row_size + 1); | |
328 | if (!top_buf) | |
329 | goto fail; | |
330 | } | |
331 | ||
332 | /* write png header */ | |
333 | AV_WB64(s->bytestream, PNGSIG); | |
334 | s->bytestream += 8; | |
335 | ||
336 | AV_WB32(s->buf, avctx->width); | |
337 | AV_WB32(s->buf + 4, avctx->height); | |
338 | s->buf[8] = bit_depth; | |
339 | s->buf[9] = color_type; | |
340 | s->buf[10] = 0; /* compression type */ | |
341 | s->buf[11] = 0; /* filter type */ | |
342 | s->buf[12] = is_progressive; /* interlace type */ | |
343 | ||
344 | png_write_chunk(&s->bytestream, MKTAG('I', 'H', 'D', 'R'), s->buf, 13); | |
345 | ||
346 | if (s->dpm) { | |
347 | AV_WB32(s->buf, s->dpm); | |
348 | AV_WB32(s->buf + 4, s->dpm); | |
349 | s->buf[8] = 1; /* unit specifier is meter */ | |
350 | } else { | |
351 | AV_WB32(s->buf, avctx->sample_aspect_ratio.num); | |
352 | AV_WB32(s->buf + 4, avctx->sample_aspect_ratio.den); | |
353 | s->buf[8] = 0; /* unit specifier is unknown */ | |
354 | } | |
355 | png_write_chunk(&s->bytestream, MKTAG('p', 'H', 'Y', 's'), s->buf, 9); | |
356 | ||
357 | /* put the palette if needed */ | |
358 | if (color_type == PNG_COLOR_TYPE_PALETTE) { | |
359 | int has_alpha, alpha, i; | |
360 | unsigned int v; | |
361 | uint32_t *palette; | |
362 | uint8_t *alpha_ptr; | |
363 | ||
364 | palette = (uint32_t *)p->data[1]; | |
365 | ptr = s->buf; | |
366 | alpha_ptr = s->buf + 256 * 3; | |
367 | has_alpha = 0; | |
368 | for (i = 0; i < 256; i++) { | |
369 | v = palette[i]; | |
370 | alpha = v >> 24; | |
371 | if (alpha != 0xff) | |
372 | has_alpha = 1; | |
373 | *alpha_ptr++ = alpha; | |
374 | bytestream_put_be24(&ptr, v); | |
375 | } | |
376 | png_write_chunk(&s->bytestream, | |
377 | MKTAG('P', 'L', 'T', 'E'), s->buf, 256 * 3); | |
378 | if (has_alpha) { | |
379 | png_write_chunk(&s->bytestream, | |
380 | MKTAG('t', 'R', 'N', 'S'), s->buf + 256 * 3, 256); | |
381 | } | |
382 | } | |
383 | ||
384 | /* now put each row */ | |
385 | s->zstream.avail_out = IOBUF_SIZE; | |
386 | s->zstream.next_out = s->buf; | |
387 | if (is_progressive) { | |
388 | int pass; | |
389 | ||
390 | for (pass = 0; pass < NB_PASSES; pass++) { | |
391 | /* NOTE: a pass is completely omitted if no pixels would be | |
392 | * output */ | |
393 | pass_row_size = ff_png_pass_row_size(pass, bits_per_pixel, avctx->width); | |
394 | if (pass_row_size > 0) { | |
395 | top = NULL; | |
396 | for (y = 0; y < avctx->height; y++) | |
397 | if ((ff_png_pass_ymask[pass] << (y & 7)) & 0x80) { | |
398 | ptr = p->data[0] + y * p->linesize[0]; | |
399 | FFSWAP(uint8_t *, progressive_buf, top_buf); | |
400 | png_get_interlaced_row(progressive_buf, pass_row_size, | |
401 | bits_per_pixel, pass, | |
402 | ptr, avctx->width); | |
403 | crow = png_choose_filter(s, crow_buf, progressive_buf, | |
404 | top, pass_row_size, bits_per_pixel >> 3); | |
405 | png_write_row(s, crow, pass_row_size + 1); | |
406 | top = progressive_buf; | |
407 | } | |
408 | } | |
409 | } | |
410 | } else { | |
411 | top = NULL; | |
412 | for (y = 0; y < avctx->height; y++) { | |
413 | ptr = p->data[0] + y * p->linesize[0]; | |
414 | crow = png_choose_filter(s, crow_buf, ptr, top, | |
415 | row_size, bits_per_pixel >> 3); | |
416 | png_write_row(s, crow, row_size + 1); | |
417 | top = ptr; | |
418 | } | |
419 | } | |
420 | /* compress last bytes */ | |
421 | for (;;) { | |
422 | ret = deflate(&s->zstream, Z_FINISH); | |
423 | if (ret == Z_OK || ret == Z_STREAM_END) { | |
424 | len = IOBUF_SIZE - s->zstream.avail_out; | |
425 | if (len > 0 && s->bytestream_end - s->bytestream > len + 100) { | |
426 | png_write_chunk(&s->bytestream, MKTAG('I', 'D', 'A', 'T'), s->buf, len); | |
427 | } | |
428 | s->zstream.avail_out = IOBUF_SIZE; | |
429 | s->zstream.next_out = s->buf; | |
430 | if (ret == Z_STREAM_END) | |
431 | break; | |
432 | } else { | |
433 | goto fail; | |
434 | } | |
435 | } | |
436 | png_write_chunk(&s->bytestream, MKTAG('I', 'E', 'N', 'D'), NULL, 0); | |
437 | ||
438 | pkt->size = s->bytestream - s->bytestream_start; | |
439 | pkt->flags |= AV_PKT_FLAG_KEY; | |
440 | *got_packet = 1; | |
441 | ret = 0; | |
442 | ||
443 | the_end: | |
444 | av_free(crow_base); | |
445 | av_free(progressive_buf); | |
446 | av_free(top_buf); | |
447 | deflateEnd(&s->zstream); | |
448 | return ret; | |
449 | fail: | |
450 | ret = -1; | |
451 | goto the_end; | |
452 | } | |
453 | ||
454 | static av_cold int png_enc_init(AVCodecContext *avctx) | |
455 | { | |
456 | PNGEncContext *s = avctx->priv_data; | |
457 | ||
458 | switch (avctx->pix_fmt) { | |
459 | case AV_PIX_FMT_RGBA: | |
460 | avctx->bits_per_coded_sample = 32; | |
461 | break; | |
462 | case AV_PIX_FMT_RGB24: | |
463 | avctx->bits_per_coded_sample = 24; | |
464 | break; | |
465 | case AV_PIX_FMT_GRAY8: | |
466 | avctx->bits_per_coded_sample = 0x28; | |
467 | break; | |
468 | case AV_PIX_FMT_MONOBLACK: | |
469 | avctx->bits_per_coded_sample = 1; | |
470 | break; | |
471 | case AV_PIX_FMT_PAL8: | |
472 | avctx->bits_per_coded_sample = 8; | |
473 | } | |
474 | ||
475 | avctx->coded_frame = av_frame_alloc(); | |
476 | if (!avctx->coded_frame) | |
477 | return AVERROR(ENOMEM); | |
478 | ||
479 | avctx->coded_frame->pict_type = AV_PICTURE_TYPE_I; | |
480 | avctx->coded_frame->key_frame = 1; | |
481 | ||
482 | ff_huffyuvencdsp_init(&s->hdsp); | |
483 | ||
484 | s->filter_type = av_clip(avctx->prediction_method, | |
485 | PNG_FILTER_VALUE_NONE, | |
486 | PNG_FILTER_VALUE_MIXED); | |
487 | if (avctx->pix_fmt == AV_PIX_FMT_MONOBLACK) | |
488 | s->filter_type = PNG_FILTER_VALUE_NONE; | |
489 | ||
490 | if (s->dpi && s->dpm) { | |
491 | av_log(avctx, AV_LOG_ERROR, "Only one of 'dpi' or 'dpm' options should be set\n"); | |
492 | return AVERROR(EINVAL); | |
493 | } else if (s->dpi) { | |
494 | s->dpm = s->dpi * 10000 / 254; | |
495 | } | |
496 | ||
497 | return 0; | |
498 | } | |
499 | ||
500 | static av_cold int png_enc_close(AVCodecContext *avctx) | |
501 | { | |
502 | av_frame_free(&avctx->coded_frame); | |
503 | return 0; | |
504 | } | |
505 | ||
506 | #define OFFSET(x) offsetof(PNGEncContext, x) | |
507 | #define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM | |
508 | static const AVOption options[] = { | |
509 | {"dpi", "Set image resolution (in dots per inch)", OFFSET(dpi), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 0x10000, VE}, | |
510 | {"dpm", "Set image resolution (in dots per meter)", OFFSET(dpm), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 0x10000, VE}, | |
511 | { NULL } | |
512 | }; | |
513 | ||
514 | static const AVClass pngenc_class = { | |
515 | .class_name = "PNG encoder", | |
516 | .item_name = av_default_item_name, | |
517 | .option = options, | |
518 | .version = LIBAVUTIL_VERSION_INT, | |
519 | }; | |
520 | ||
521 | AVCodec ff_png_encoder = { | |
522 | .name = "png", | |
523 | .long_name = NULL_IF_CONFIG_SMALL("PNG (Portable Network Graphics) image"), | |
524 | .type = AVMEDIA_TYPE_VIDEO, | |
525 | .id = AV_CODEC_ID_PNG, | |
526 | .priv_data_size = sizeof(PNGEncContext), | |
527 | .init = png_enc_init, | |
528 | .close = png_enc_close, | |
529 | .encode2 = encode_frame, | |
530 | .capabilities = CODEC_CAP_FRAME_THREADS | CODEC_CAP_INTRA_ONLY, | |
531 | .pix_fmts = (const enum AVPixelFormat[]) { | |
532 | AV_PIX_FMT_RGB24, AV_PIX_FMT_RGBA, | |
533 | AV_PIX_FMT_RGB48BE, AV_PIX_FMT_RGBA64BE, | |
534 | AV_PIX_FMT_PAL8, | |
535 | AV_PIX_FMT_GRAY8, AV_PIX_FMT_GRAY8A, | |
536 | AV_PIX_FMT_GRAY16BE, | |
537 | AV_PIX_FMT_MONOBLACK, AV_PIX_FMT_NONE | |
538 | }, | |
539 | .priv_class = &pngenc_class, | |
540 | }; |