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 //#define DEBUG
23
24 #include "libavutil/bprint.h"
25 #include "libavutil/imgutils.h"
26 #include "avcodec.h"
27 #include "bytestream.h"
28 #include "internal.h"
29 #include "png.h"
30 #include "pngdsp.h"
31 #include "thread.h"
32
33 #include <zlib.h>
34
35 #ifndef SIZE_MAX
36 # ifdef __SIZE_MAX__
37 # define SIZE_MAX __SIZE_MAX__
38 # else
39 # error no SIZE_MAX
40 # endif
41 #endif
42
43 typedef struct PNGDecContext {
44 PNGDSPContext dsp;
45 AVCodecContext *avctx;
46
47 GetByteContext gb;
48 ThreadFrame last_picture;
49 ThreadFrame picture;
50
51 int state;
52 int width, height;
53 int bit_depth;
54 int color_type;
55 int compression_type;
56 int interlace_type;
57 int filter_type;
58 int channels;
59 int bits_per_pixel;
60 int bpp;
61
62 uint8_t *image_buf;
63 int image_linesize;
64 uint32_t palette[256];
65 uint8_t *crow_buf;
66 uint8_t *last_row;
67 unsigned int last_row_size;
68 uint8_t *tmp_row;
69 unsigned int tmp_row_size;
70 uint8_t *buffer;
71 int buffer_size;
72 int pass;
73 int crow_size; /* compressed row size (include filter type) */
74 int row_size; /* decompressed row size */
75 int pass_row_size; /* decompress row size of the current pass */
76 int y;
77 z_stream zstream;
78 } PNGDecContext;
79
80 /* Mask to determine which pixels are valid in a pass */
81 static const uint8_t png_pass_mask[NB_PASSES] = {
82 0x01, 0x01, 0x11, 0x11, 0x55, 0x55, 0xff,
83 };
84
85 /* Mask to determine which y pixels can be written in a pass */
86 static const uint8_t png_pass_dsp_ymask[NB_PASSES] = {
87 0xff, 0xff, 0x0f, 0xff, 0x33, 0xff, 0x55,
88 };
89
90 /* Mask to determine which pixels to overwrite while displaying */
91 static const uint8_t png_pass_dsp_mask[NB_PASSES] = {
92 0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff
93 };
94
95 /* NOTE: we try to construct a good looking image at each pass. width
96 * is the original image width. We also do pixel format conversion at
97 * this stage */
png_put_interlaced_row(uint8_t * dst,int width,int bits_per_pixel,int pass,int color_type,const uint8_t * src)98 static void png_put_interlaced_row(uint8_t *dst, int width,
99 int bits_per_pixel, int pass,
100 int color_type, const uint8_t *src)
101 {
102 int x, mask, dsp_mask, j, src_x, b, bpp;
103 uint8_t *d;
104 const uint8_t *s;
105
106 mask = png_pass_mask[pass];
107 dsp_mask = png_pass_dsp_mask[pass];
108
109 switch (bits_per_pixel) {
110 case 1:
111 src_x = 0;
112 for (x = 0; x < width; x++) {
113 j = (x & 7);
114 if ((dsp_mask << j) & 0x80) {
115 b = (src[src_x >> 3] >> (7 - (src_x & 7))) & 1;
116 dst[x >> 3] &= 0xFF7F>>j;
117 dst[x >> 3] |= b << (7 - j);
118 }
119 if ((mask << j) & 0x80)
120 src_x++;
121 }
122 break;
123 case 2:
124 src_x = 0;
125 for (x = 0; x < width; x++) {
126 int j2 = 2 * (x & 3);
127 j = (x & 7);
128 if ((dsp_mask << j) & 0x80) {
129 b = (src[src_x >> 2] >> (6 - 2*(src_x & 3))) & 3;
130 dst[x >> 2] &= 0xFF3F>>j2;
131 dst[x >> 2] |= b << (6 - j2);
132 }
133 if ((mask << j) & 0x80)
134 src_x++;
135 }
136 break;
137 case 4:
138 src_x = 0;
139 for (x = 0; x < width; x++) {
140 int j2 = 4*(x&1);
141 j = (x & 7);
142 if ((dsp_mask << j) & 0x80) {
143 b = (src[src_x >> 1] >> (4 - 4*(src_x & 1))) & 15;
144 dst[x >> 1] &= 0xFF0F>>j2;
145 dst[x >> 1] |= b << (4 - j2);
146 }
147 if ((mask << j) & 0x80)
148 src_x++;
149 }
150 break;
151 default:
152 bpp = bits_per_pixel >> 3;
153 d = dst;
154 s = src;
155 for (x = 0; x < width; x++) {
156 j = x & 7;
157 if ((dsp_mask << j) & 0x80) {
158 memcpy(d, s, bpp);
159 }
160 d += bpp;
161 if ((mask << j) & 0x80)
162 s += bpp;
163 }
164 break;
165 }
166 }
167
ff_add_png_paeth_prediction(uint8_t * dst,uint8_t * src,uint8_t * top,int w,int bpp)168 void ff_add_png_paeth_prediction(uint8_t *dst, uint8_t *src, uint8_t *top,
169 int w, int bpp)
170 {
171 int i;
172 for (i = 0; i < w; i++) {
173 int a, b, c, p, pa, pb, pc;
174
175 a = dst[i - bpp];
176 b = top[i];
177 c = top[i - bpp];
178
179 p = b - c;
180 pc = a - c;
181
182 pa = abs(p);
183 pb = abs(pc);
184 pc = abs(p + pc);
185
186 if (pa <= pb && pa <= pc)
187 p = a;
188 else if (pb <= pc)
189 p = b;
190 else
191 p = c;
192 dst[i] = p + src[i];
193 }
194 }
195
196 #define UNROLL1(bpp, op) \
197 { \
198 r = dst[0]; \
199 if (bpp >= 2) \
200 g = dst[1]; \
201 if (bpp >= 3) \
202 b = dst[2]; \
203 if (bpp >= 4) \
204 a = dst[3]; \
205 for (; i <= size - bpp; i += bpp) { \
206 dst[i + 0] = r = op(r, src[i + 0], last[i + 0]); \
207 if (bpp == 1) \
208 continue; \
209 dst[i + 1] = g = op(g, src[i + 1], last[i + 1]); \
210 if (bpp == 2) \
211 continue; \
212 dst[i + 2] = b = op(b, src[i + 2], last[i + 2]); \
213 if (bpp == 3) \
214 continue; \
215 dst[i + 3] = a = op(a, src[i + 3], last[i + 3]); \
216 } \
217 }
218
219 #define UNROLL_FILTER(op) \
220 if (bpp == 1) { \
221 UNROLL1(1, op) \
222 } else if (bpp == 2) { \
223 UNROLL1(2, op) \
224 } else if (bpp == 3) { \
225 UNROLL1(3, op) \
226 } else if (bpp == 4) { \
227 UNROLL1(4, op) \
228 } \
229 for (; i < size; i++) { \
230 dst[i] = op(dst[i - bpp], src[i], last[i]); \
231 }
232
233 /* NOTE: 'dst' can be equal to 'last' */
png_filter_row(PNGDSPContext * dsp,uint8_t * dst,int filter_type,uint8_t * src,uint8_t * last,int size,int bpp)234 static void png_filter_row(PNGDSPContext *dsp, uint8_t *dst, int filter_type,
235 uint8_t *src, uint8_t *last, int size, int bpp)
236 {
237 int i, p, r, g, b, a;
238
239 switch (filter_type) {
240 case PNG_FILTER_VALUE_NONE:
241 memcpy(dst, src, size);
242 break;
243 case PNG_FILTER_VALUE_SUB:
244 for (i = 0; i < bpp; i++)
245 dst[i] = src[i];
246 if (bpp == 4) {
247 p = *(int *)dst;
248 for (; i < size; i += bpp) {
249 unsigned s = *(int *)(src + i);
250 p = ((s & 0x7f7f7f7f) + (p & 0x7f7f7f7f)) ^ ((s ^ p) & 0x80808080);
251 *(int *)(dst + i) = p;
252 }
253 } else {
254 #define OP_SUB(x, s, l) ((x) + (s))
255 UNROLL_FILTER(OP_SUB);
256 }
257 break;
258 case PNG_FILTER_VALUE_UP:
259 dsp->add_bytes_l2(dst, src, last, size);
260 break;
261 case PNG_FILTER_VALUE_AVG:
262 for (i = 0; i < bpp; i++) {
263 p = (last[i] >> 1);
264 dst[i] = p + src[i];
265 }
266 #define OP_AVG(x, s, l) (((((x) + (l)) >> 1) + (s)) & 0xff)
267 UNROLL_FILTER(OP_AVG);
268 break;
269 case PNG_FILTER_VALUE_PAETH:
270 for (i = 0; i < bpp; i++) {
271 p = last[i];
272 dst[i] = p + src[i];
273 }
274 if (bpp > 2 && size > 4) {
275 /* would write off the end of the array if we let it process
276 * the last pixel with bpp=3 */
277 int w = bpp == 4 ? size : size - 3;
278 dsp->add_paeth_prediction(dst + i, src + i, last + i, w - i, bpp);
279 i = w;
280 }
281 ff_add_png_paeth_prediction(dst + i, src + i, last + i, size - i, bpp);
282 break;
283 }
284 }
285
286 /* This used to be called "deloco" in FFmpeg
287 * and is actually an inverse reversible colorspace transformation */
288 #define YUV2RGB(NAME, TYPE) \
289 static void deloco_ ## NAME(TYPE *dst, int size, int alpha) \
290 { \
291 int i; \
292 for (i = 0; i < size; i += 3 + alpha) { \
293 int g = dst [i + 1]; \
294 dst[i + 0] += g; \
295 dst[i + 2] += g; \
296 } \
297 }
298
YUV2RGB(rgb8,uint8_t)299 YUV2RGB(rgb8, uint8_t)
300 YUV2RGB(rgb16, uint16_t)
301
302 /* process exactly one decompressed row */
303 static void png_handle_row(PNGDecContext *s)
304 {
305 uint8_t *ptr, *last_row;
306 int got_line;
307
308 if (!s->interlace_type) {
309 ptr = s->image_buf + s->image_linesize * s->y;
310 if (s->y == 0)
311 last_row = s->last_row;
312 else
313 last_row = ptr - s->image_linesize;
314
315 png_filter_row(&s->dsp, ptr, s->crow_buf[0], s->crow_buf + 1,
316 last_row, s->row_size, s->bpp);
317 /* loco lags by 1 row so that it doesn't interfere with top prediction */
318 if (s->filter_type == PNG_FILTER_TYPE_LOCO && s->y > 0) {
319 if (s->bit_depth == 16) {
320 deloco_rgb16((uint16_t *)(ptr - s->image_linesize), s->row_size / 2,
321 s->color_type == PNG_COLOR_TYPE_RGB_ALPHA);
322 } else {
323 deloco_rgb8(ptr - s->image_linesize, s->row_size,
324 s->color_type == PNG_COLOR_TYPE_RGB_ALPHA);
325 }
326 }
327 s->y++;
328 if (s->y == s->height) {
329 s->state |= PNG_ALLIMAGE;
330 if (s->filter_type == PNG_FILTER_TYPE_LOCO) {
331 if (s->bit_depth == 16) {
332 deloco_rgb16((uint16_t *)ptr, s->row_size / 2,
333 s->color_type == PNG_COLOR_TYPE_RGB_ALPHA);
334 } else {
335 deloco_rgb8(ptr, s->row_size,
336 s->color_type == PNG_COLOR_TYPE_RGB_ALPHA);
337 }
338 }
339 }
340 } else {
341 got_line = 0;
342 for (;;) {
343 ptr = s->image_buf + s->image_linesize * s->y;
344 if ((ff_png_pass_ymask[s->pass] << (s->y & 7)) & 0x80) {
345 /* if we already read one row, it is time to stop to
346 * wait for the next one */
347 if (got_line)
348 break;
349 png_filter_row(&s->dsp, s->tmp_row, s->crow_buf[0], s->crow_buf + 1,
350 s->last_row, s->pass_row_size, s->bpp);
351 FFSWAP(uint8_t *, s->last_row, s->tmp_row);
352 FFSWAP(unsigned int, s->last_row_size, s->tmp_row_size);
353 got_line = 1;
354 }
355 if ((png_pass_dsp_ymask[s->pass] << (s->y & 7)) & 0x80) {
356 png_put_interlaced_row(ptr, s->width, s->bits_per_pixel, s->pass,
357 s->color_type, s->last_row);
358 }
359 s->y++;
360 if (s->y == s->height) {
361 memset(s->last_row, 0, s->row_size);
362 for (;;) {
363 if (s->pass == NB_PASSES - 1) {
364 s->state |= PNG_ALLIMAGE;
365 goto the_end;
366 } else {
367 s->pass++;
368 s->y = 0;
369 s->pass_row_size = ff_png_pass_row_size(s->pass,
370 s->bits_per_pixel,
371 s->width);
372 s->crow_size = s->pass_row_size + 1;
373 if (s->pass_row_size != 0)
374 break;
375 /* skip pass if empty row */
376 }
377 }
378 }
379 }
380 the_end:;
381 }
382 }
383
png_decode_idat(PNGDecContext * s,int length)384 static int png_decode_idat(PNGDecContext *s, int length)
385 {
386 int ret;
387 s->zstream.avail_in = FFMIN(length, bytestream2_get_bytes_left(&s->gb));
388 s->zstream.next_in = (unsigned char *)s->gb.buffer;
389 bytestream2_skip(&s->gb, length);
390
391 /* decode one line if possible */
392 while (s->zstream.avail_in > 0) {
393 ret = inflate(&s->zstream, Z_PARTIAL_FLUSH);
394 if (ret != Z_OK && ret != Z_STREAM_END) {
395 av_log(s->avctx, AV_LOG_ERROR, "inflate returned error %d\n", ret);
396 return AVERROR_EXTERNAL;
397 }
398 if (s->zstream.avail_out == 0) {
399 if (!(s->state & PNG_ALLIMAGE)) {
400 png_handle_row(s);
401 }
402 s->zstream.avail_out = s->crow_size;
403 s->zstream.next_out = s->crow_buf;
404 }
405 if (ret == Z_STREAM_END && s->zstream.avail_in > 0) {
406 av_log(NULL, AV_LOG_WARNING,
407 "%d undecompressed bytes left in buffer\n", s->zstream.avail_in);
408 return 0;
409 }
410 }
411 return 0;
412 }
413
decode_zbuf(AVBPrint * bp,const uint8_t * data,const uint8_t * data_end)414 static int decode_zbuf(AVBPrint *bp, const uint8_t *data,
415 const uint8_t *data_end)
416 {
417 z_stream zstream;
418 unsigned char *buf;
419 unsigned buf_size;
420 int ret;
421
422 zstream.zalloc = ff_png_zalloc;
423 zstream.zfree = ff_png_zfree;
424 zstream.opaque = NULL;
425 if (inflateInit(&zstream) != Z_OK)
426 return AVERROR_EXTERNAL;
427 zstream.next_in = (unsigned char *)data;
428 zstream.avail_in = data_end - data;
429 av_bprint_init(bp, 0, -1);
430
431 while (zstream.avail_in > 0) {
432 av_bprint_get_buffer(bp, 1, &buf, &buf_size);
433 if (!buf_size) {
434 ret = AVERROR(ENOMEM);
435 goto fail;
436 }
437 zstream.next_out = buf;
438 zstream.avail_out = buf_size;
439 ret = inflate(&zstream, Z_PARTIAL_FLUSH);
440 if (ret != Z_OK && ret != Z_STREAM_END) {
441 ret = AVERROR_EXTERNAL;
442 goto fail;
443 }
444 bp->len += zstream.next_out - buf;
445 if (ret == Z_STREAM_END)
446 break;
447 }
448 inflateEnd(&zstream);
449 bp->str[bp->len] = 0;
450 return 0;
451
452 fail:
453 inflateEnd(&zstream);
454 av_bprint_finalize(bp, NULL);
455 return ret;
456 }
457
iso88591_to_utf8(const uint8_t * in,size_t size_in)458 static uint8_t *iso88591_to_utf8(const uint8_t *in, size_t size_in)
459 {
460 size_t extra = 0, i;
461 uint8_t *out, *q;
462
463 for (i = 0; i < size_in; i++)
464 extra += in[i] >= 0x80;
465 if (size_in == SIZE_MAX || extra > SIZE_MAX - size_in - 1)
466 return NULL;
467 q = out = av_malloc(size_in + extra + 1);
468 if (!out)
469 return NULL;
470 for (i = 0; i < size_in; i++) {
471 if (in[i] >= 0x80) {
472 *(q++) = 0xC0 | (in[i] >> 6);
473 *(q++) = 0x80 | (in[i] & 0x3F);
474 } else {
475 *(q++) = in[i];
476 }
477 }
478 *(q++) = 0;
479 return out;
480 }
481
482 typedef union {
483 uint8_t *t_uint8_t;
484 char *t_char;
485 } u_uint8_char;
486
decode_text_chunk(PNGDecContext * s,uint32_t length,int compressed,AVDictionary ** dict)487 static int decode_text_chunk(PNGDecContext *s, uint32_t length, int compressed,
488 AVDictionary **dict)
489 {
490 int ret, method;
491 const uint8_t *data = s->gb.buffer;
492 const uint8_t *data_end = data + length;
493 const uint8_t *keyword = data;
494 const uint8_t *keyword_end = memchr(keyword, 0, data_end - keyword);
495 uint8_t *kw_utf8 = NULL, *txt_utf8 = NULL;
496 u_uint8_char text;
497 unsigned text_len;
498 AVBPrint bp;
499
500 if (!keyword_end)
501 return AVERROR_INVALIDDATA;
502 data = keyword_end + 1;
503
504 if (compressed) {
505 if (data == data_end)
506 return AVERROR_INVALIDDATA;
507 method = *(data++);
508 if (method)
509 return AVERROR_INVALIDDATA;
510 if ((ret = decode_zbuf(&bp, data, data_end)) < 0)
511 return ret;
512 text_len = bp.len;
513 av_bprint_finalize(&bp, (char **)&text);
514 if (!text.t_uint8_t)
515 return AVERROR(ENOMEM);
516 } else {
517 text.t_uint8_t = (uint8_t *)data;
518 text_len = data_end - text.t_uint8_t;
519 }
520
521 kw_utf8 = iso88591_to_utf8(keyword, keyword_end - keyword);
522 txt_utf8 = iso88591_to_utf8(text.t_uint8_t, text_len);
523 if (text.t_uint8_t != data)
524 av_free(text.t_uint8_t);
525 if (!(kw_utf8 && txt_utf8)) {
526 av_free(kw_utf8);
527 av_free(txt_utf8);
528 return AVERROR(ENOMEM);
529 }
530
531 av_dict_set(dict, kw_utf8, txt_utf8,
532 AV_DICT_DONT_STRDUP_KEY | AV_DICT_DONT_STRDUP_VAL);
533 return 0;
534 }
535
decode_frame(AVCodecContext * avctx,void * data,int * got_frame,AVPacket * avpkt)536 static int decode_frame(AVCodecContext *avctx,
537 void *data, int *got_frame,
538 AVPacket *avpkt)
539 {
540 PNGDecContext *const s = avctx->priv_data;
541 const uint8_t *buf = avpkt->data;
542 int buf_size = avpkt->size;
543 AVFrame *p;
544 AVDictionary *metadata = NULL;
545 uint32_t tag, length;
546 int64_t sig;
547 int ret;
548
549 ff_thread_release_buffer(avctx, &s->last_picture);
550 FFSWAP(ThreadFrame, s->picture, s->last_picture);
551 p = s->picture.f;
552
553 bytestream2_init(&s->gb, buf, buf_size);
554
555 /* check signature */
556 sig = bytestream2_get_be64(&s->gb);
557 if (sig != PNGSIG &&
558 sig != MNGSIG) {
559 av_log(avctx, AV_LOG_ERROR, "Missing png signature\n");
560 return AVERROR_INVALIDDATA;
561 }
562
563 s->y = s->state = 0;
564
565 /* init the zlib */
566 s->zstream.zalloc = ff_png_zalloc;
567 s->zstream.zfree = ff_png_zfree;
568 s->zstream.opaque = NULL;
569 ret = inflateInit(&s->zstream);
570 if (ret != Z_OK) {
571 av_log(avctx, AV_LOG_ERROR, "inflateInit returned error %d\n", ret);
572 return AVERROR_EXTERNAL;
573 }
574 for (;;) {
575 if (bytestream2_get_bytes_left(&s->gb) <= 0) {
576 av_log(avctx, AV_LOG_ERROR, "%d bytes left\n", bytestream2_get_bytes_left(&s->gb));
577 if ( s->state & PNG_ALLIMAGE
578 && avctx->strict_std_compliance <= FF_COMPLIANCE_NORMAL)
579 goto exit_loop;
580 goto fail;
581 }
582
583 length = bytestream2_get_be32(&s->gb);
584 if (length > 0x7fffffff || length > bytestream2_get_bytes_left(&s->gb)) {
585 av_log(avctx, AV_LOG_ERROR, "chunk too big\n");
586 goto fail;
587 }
588 tag = bytestream2_get_le32(&s->gb);
589 if (avctx->debug & FF_DEBUG_STARTCODE)
590 av_log(avctx, AV_LOG_DEBUG, "png: tag=%c%c%c%c length=%u\n",
591 (tag & 0xff),
592 ((tag >> 8) & 0xff),
593 ((tag >> 16) & 0xff),
594 ((tag >> 24) & 0xff), length);
595 switch (tag) {
596 case MKTAG('I', 'H', 'D', 'R'):
597 if (length != 13)
598 goto fail;
599 s->width = bytestream2_get_be32(&s->gb);
600 s->height = bytestream2_get_be32(&s->gb);
601 if (av_image_check_size(s->width, s->height, 0, avctx)) {
602 s->width = s->height = 0;
603 av_log(avctx, AV_LOG_ERROR, "Invalid image size\n");
604 goto fail;
605 }
606 s->bit_depth = bytestream2_get_byte(&s->gb);
607 s->color_type = bytestream2_get_byte(&s->gb);
608 s->compression_type = bytestream2_get_byte(&s->gb);
609 s->filter_type = bytestream2_get_byte(&s->gb);
610 s->interlace_type = bytestream2_get_byte(&s->gb);
611 bytestream2_skip(&s->gb, 4); /* crc */
612 s->state |= PNG_IHDR;
613 if (avctx->debug & FF_DEBUG_PICT_INFO)
614 av_log(avctx, AV_LOG_DEBUG, "width=%d height=%d depth=%d color_type=%d "
615 "compression_type=%d filter_type=%d interlace_type=%d\n",
616 s->width, s->height, s->bit_depth, s->color_type,
617 s->compression_type, s->filter_type, s->interlace_type);
618 break;
619 case MKTAG('p', 'H', 'Y', 's'):
620 if (s->state & PNG_IDAT) {
621 av_log(avctx, AV_LOG_ERROR, "pHYs after IDAT\n");
622 goto fail;
623 }
624 avctx->sample_aspect_ratio.num = bytestream2_get_be32(&s->gb);
625 avctx->sample_aspect_ratio.den = bytestream2_get_be32(&s->gb);
626 if (avctx->sample_aspect_ratio.num < 0 || avctx->sample_aspect_ratio.den < 0)
627 avctx->sample_aspect_ratio = (AVRational){ 0, 1 };
628 bytestream2_skip(&s->gb, 1); /* unit specifier */
629 bytestream2_skip(&s->gb, 4); /* crc */
630 break;
631 case MKTAG('I', 'D', 'A', 'T'):
632 if (!(s->state & PNG_IHDR)) {
633 av_log(avctx, AV_LOG_ERROR, "IDAT without IHDR\n");
634 goto fail;
635 }
636 if (!(s->state & PNG_IDAT)) {
637 /* init image info */
638 avctx->width = s->width;
639 avctx->height = s->height;
640
641 s->channels = ff_png_get_nb_channels(s->color_type);
642 s->bits_per_pixel = s->bit_depth * s->channels;
643 s->bpp = (s->bits_per_pixel + 7) >> 3;
644 s->row_size = (avctx->width * s->bits_per_pixel + 7) >> 3;
645
646 if ((s->bit_depth == 2 || s->bit_depth == 4 || s->bit_depth == 8) &&
647 s->color_type == PNG_COLOR_TYPE_RGB) {
648 avctx->pix_fmt = AV_PIX_FMT_RGB24;
649 } else if ((s->bit_depth == 2 || s->bit_depth == 4 || s->bit_depth == 8) &&
650 s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
651 avctx->pix_fmt = AV_PIX_FMT_RGBA;
652 } else if ((s->bit_depth == 2 || s->bit_depth == 4 || s->bit_depth == 8) &&
653 s->color_type == PNG_COLOR_TYPE_GRAY) {
654 avctx->pix_fmt = AV_PIX_FMT_GRAY8;
655 } else if (s->bit_depth == 16 &&
656 s->color_type == PNG_COLOR_TYPE_GRAY) {
657 avctx->pix_fmt = AV_PIX_FMT_GRAY16BE;
658 } else if (s->bit_depth == 16 &&
659 s->color_type == PNG_COLOR_TYPE_RGB) {
660 avctx->pix_fmt = AV_PIX_FMT_RGB48BE;
661 } else if (s->bit_depth == 16 &&
662 s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
663 avctx->pix_fmt = AV_PIX_FMT_RGBA64BE;
664 } else if ((s->bits_per_pixel == 1 || s->bits_per_pixel == 2 || s->bits_per_pixel == 4 || s->bits_per_pixel == 8) &&
665 s->color_type == PNG_COLOR_TYPE_PALETTE) {
666 avctx->pix_fmt = AV_PIX_FMT_PAL8;
667 } else if (s->bit_depth == 1 && s->bits_per_pixel == 1) {
668 avctx->pix_fmt = AV_PIX_FMT_MONOBLACK;
669 } else if (s->bit_depth == 8 &&
670 s->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) {
671 avctx->pix_fmt = AV_PIX_FMT_YA8;
672 } else if (s->bit_depth == 16 &&
673 s->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) {
674 avctx->pix_fmt = AV_PIX_FMT_YA16BE;
675 } else {
676 av_log(avctx, AV_LOG_ERROR, "unsupported bit depth %d "
677 "and color type %d\n",
678 s->bit_depth, s->color_type);
679 goto fail;
680 }
681
682 if (ff_thread_get_buffer(avctx, &s->picture, AV_GET_BUFFER_FLAG_REF) < 0)
683 goto fail;
684 ff_thread_finish_setup(avctx);
685
686 p->pict_type = AV_PICTURE_TYPE_I;
687 p->key_frame = 1;
688 p->interlaced_frame = !!s->interlace_type;
689
690 /* compute the compressed row size */
691 if (!s->interlace_type) {
692 s->crow_size = s->row_size + 1;
693 } else {
694 s->pass = 0;
695 s->pass_row_size = ff_png_pass_row_size(s->pass,
696 s->bits_per_pixel,
697 s->width);
698 s->crow_size = s->pass_row_size + 1;
699 }
700 av_dlog(avctx, "row_size=%d crow_size =%d\n",
701 s->row_size, s->crow_size);
702 s->image_buf = p->data[0];
703 s->image_linesize = p->linesize[0];
704 /* copy the palette if needed */
705 if (avctx->pix_fmt == AV_PIX_FMT_PAL8)
706 memcpy(p->data[1], s->palette, 256 * sizeof(uint32_t));
707 /* empty row is used if differencing to the first row */
708 av_fast_padded_mallocz(&s->last_row, &s->last_row_size, s->row_size);
709 if (!s->last_row)
710 goto fail;
711 if (s->interlace_type ||
712 s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
713 av_fast_padded_malloc(&s->tmp_row, &s->tmp_row_size, s->row_size);
714 if (!s->tmp_row)
715 goto fail;
716 }
717 /* compressed row */
718 av_fast_padded_malloc(&s->buffer, &s->buffer_size, s->row_size + 16);
719 if (!s->buffer)
720 goto fail;
721
722 /* we want crow_buf+1 to be 16-byte aligned */
723 s->crow_buf = s->buffer + 15;
724 s->zstream.avail_out = s->crow_size;
725 s->zstream.next_out = s->crow_buf;
726 }
727 s->state |= PNG_IDAT;
728 if (png_decode_idat(s, length) < 0)
729 goto fail;
730 bytestream2_skip(&s->gb, 4); /* crc */
731 break;
732 case MKTAG('P', 'L', 'T', 'E'):
733 {
734 int n, i, r, g, b;
735
736 if ((length % 3) != 0 || length > 256 * 3)
737 goto skip_tag;
738 /* read the palette */
739 n = length / 3;
740 for (i = 0; i < n; i++) {
741 r = bytestream2_get_byte(&s->gb);
742 g = bytestream2_get_byte(&s->gb);
743 b = bytestream2_get_byte(&s->gb);
744 s->palette[i] = (0xFFU << 24) | (r << 16) | (g << 8) | b;
745 }
746 for (; i < 256; i++)
747 s->palette[i] = (0xFFU << 24);
748 s->state |= PNG_PLTE;
749 bytestream2_skip(&s->gb, 4); /* crc */
750 }
751 break;
752 case MKTAG('t', 'R', 'N', 'S'):
753 {
754 int v, i;
755
756 /* read the transparency. XXX: Only palette mode supported */
757 if (s->color_type != PNG_COLOR_TYPE_PALETTE ||
758 length > 256 ||
759 !(s->state & PNG_PLTE))
760 goto skip_tag;
761 for (i = 0; i < length; i++) {
762 v = bytestream2_get_byte(&s->gb);
763 s->palette[i] = (s->palette[i] & 0x00ffffff) | (v << 24);
764 }
765 bytestream2_skip(&s->gb, 4); /* crc */
766 }
767 break;
768 case MKTAG('t', 'E', 'X', 't'):
769 if (decode_text_chunk(s, length, 0, &metadata) < 0)
770 av_log(avctx, AV_LOG_WARNING, "Broken tEXt chunk\n");
771 bytestream2_skip(&s->gb, length + 4);
772 break;
773 case MKTAG('z', 'T', 'X', 't'):
774 if (decode_text_chunk(s, length, 1, &metadata) < 0)
775 av_log(avctx, AV_LOG_WARNING, "Broken zTXt chunk\n");
776 bytestream2_skip(&s->gb, length + 4);
777 break;
778 case MKTAG('I', 'E', 'N', 'D'):
779 if (!(s->state & PNG_ALLIMAGE))
780 av_log(avctx, AV_LOG_ERROR, "IEND without all image\n");
781 if (!(s->state & (PNG_ALLIMAGE|PNG_IDAT))) {
782 goto fail;
783 }
784 bytestream2_skip(&s->gb, 4); /* crc */
785 goto exit_loop;
786 default:
787 /* skip tag */
788 skip_tag:
789 bytestream2_skip(&s->gb, length + 4);
790 break;
791 }
792 }
793 exit_loop:
794
795 if (s->bits_per_pixel == 1 && s->color_type == PNG_COLOR_TYPE_PALETTE){
796 int i, j, k;
797 uint8_t *pd = p->data[0];
798 for (j = 0; j < s->height; j++) {
799 i = s->width / 8;
800 for (k = 7; k >= 1; k--)
801 if ((s->width&7) >= k)
802 pd[8*i + k - 1] = (pd[i]>>8-k) & 1;
803 for (i--; i >= 0; i--) {
804 pd[8*i + 7]= pd[i] & 1;
805 pd[8*i + 6]= (pd[i]>>1) & 1;
806 pd[8*i + 5]= (pd[i]>>2) & 1;
807 pd[8*i + 4]= (pd[i]>>3) & 1;
808 pd[8*i + 3]= (pd[i]>>4) & 1;
809 pd[8*i + 2]= (pd[i]>>5) & 1;
810 pd[8*i + 1]= (pd[i]>>6) & 1;
811 pd[8*i + 0]= pd[i]>>7;
812 }
813 pd += s->image_linesize;
814 }
815 }
816 if (s->bits_per_pixel == 2){
817 int i, j;
818 uint8_t *pd = p->data[0];
819 for (j = 0; j < s->height; j++) {
820 i = s->width / 4;
821 if (s->color_type == PNG_COLOR_TYPE_PALETTE){
822 if ((s->width&3) >= 3) pd[4*i + 2]= (pd[i] >> 2) & 3;
823 if ((s->width&3) >= 2) pd[4*i + 1]= (pd[i] >> 4) & 3;
824 if ((s->width&3) >= 1) pd[4*i + 0]= pd[i] >> 6;
825 for (i--; i >= 0; i--) {
826 pd[4*i + 3]= pd[i] & 3;
827 pd[4*i + 2]= (pd[i]>>2) & 3;
828 pd[4*i + 1]= (pd[i]>>4) & 3;
829 pd[4*i + 0]= pd[i]>>6;
830 }
831 } else {
832 if ((s->width&3) >= 3) pd[4*i + 2]= ((pd[i]>>2) & 3)*0x55;
833 if ((s->width&3) >= 2) pd[4*i + 1]= ((pd[i]>>4) & 3)*0x55;
834 if ((s->width&3) >= 1) pd[4*i + 0]= ( pd[i]>>6 )*0x55;
835 for (i--; i >= 0; i--) {
836 pd[4*i + 3]= ( pd[i] & 3)*0x55;
837 pd[4*i + 2]= ((pd[i]>>2) & 3)*0x55;
838 pd[4*i + 1]= ((pd[i]>>4) & 3)*0x55;
839 pd[4*i + 0]= ( pd[i]>>6 )*0x55;
840 }
841 }
842 pd += s->image_linesize;
843 }
844 }
845 if (s->bits_per_pixel == 4){
846 int i, j;
847 uint8_t *pd = p->data[0];
848 for (j = 0; j < s->height; j++) {
849 i = s->width/2;
850 if (s->color_type == PNG_COLOR_TYPE_PALETTE){
851 if (s->width&1) pd[2*i+0]= pd[i]>>4;
852 for (i--; i >= 0; i--) {
853 pd[2*i + 1] = pd[i] & 15;
854 pd[2*i + 0] = pd[i] >> 4;
855 }
856 } else {
857 if (s->width & 1) pd[2*i + 0]= (pd[i] >> 4) * 0x11;
858 for (i--; i >= 0; i--) {
859 pd[2*i + 1] = (pd[i] & 15) * 0x11;
860 pd[2*i + 0] = (pd[i] >> 4) * 0x11;
861 }
862 }
863 pd += s->image_linesize;
864 }
865 }
866
867 /* handle p-frames only if a predecessor frame is available */
868 if (s->last_picture.f->data[0]) {
869 if ( !(avpkt->flags & AV_PKT_FLAG_KEY) && avctx->codec_tag != AV_RL32("MPNG")
870 && s->last_picture.f->width == p->width
871 && s->last_picture.f->height== p->height
872 && s->last_picture.f->format== p->format
873 ) {
874 int i, j;
875 uint8_t *pd = p->data[0];
876 uint8_t *pd_last = s->last_picture.f->data[0];
877 int ls = FFMIN(av_image_get_linesize(p->format, s->width, 0), s->width * s->bpp);
878
879 ff_thread_await_progress(&s->last_picture, INT_MAX, 0);
880 for (j = 0; j < s->height; j++) {
881 for (i = 0; i < ls; i++)
882 pd[i] += pd_last[i];
883 pd += s->image_linesize;
884 pd_last += s->image_linesize;
885 }
886 }
887 }
888 ff_thread_report_progress(&s->picture, INT_MAX, 0);
889
890 av_frame_set_metadata(p, metadata);
891 metadata = NULL;
892
893 if ((ret = av_frame_ref(data, s->picture.f)) < 0)
894 return ret;
895
896 *got_frame = 1;
897
898 ret = bytestream2_tell(&s->gb);
899 the_end:
900 inflateEnd(&s->zstream);
901 s->crow_buf = NULL;
902 return ret;
903 fail:
904 av_dict_free(&metadata);
905 ff_thread_report_progress(&s->picture, INT_MAX, 0);
906 ret = AVERROR_INVALIDDATA;
907 goto the_end;
908 }
909
update_thread_context(AVCodecContext * dst,const AVCodecContext * src)910 static int update_thread_context(AVCodecContext *dst, const AVCodecContext *src)
911 {
912 PNGDecContext *psrc = src->priv_data;
913 PNGDecContext *pdst = dst->priv_data;
914
915 if (dst == src)
916 return 0;
917
918 ff_thread_release_buffer(dst, &pdst->picture);
919 if (psrc->picture.f->data[0])
920 return ff_thread_ref_frame(&pdst->picture, &psrc->picture);
921
922 return 0;
923 }
924
png_dec_init(AVCodecContext * avctx)925 static av_cold int png_dec_init(AVCodecContext *avctx)
926 {
927 PNGDecContext *s = avctx->priv_data;
928
929 s->avctx = avctx;
930 s->last_picture.f = av_frame_alloc();
931 s->picture.f = av_frame_alloc();
932 if (!s->last_picture.f || !s->picture.f)
933 return AVERROR(ENOMEM);
934
935 if (!avctx->internal->is_copy) {
936 avctx->internal->allocate_progress = 1;
937 ff_pngdsp_init(&s->dsp);
938 }
939
940 return 0;
941 }
942
png_dec_end(AVCodecContext * avctx)943 static av_cold int png_dec_end(AVCodecContext *avctx)
944 {
945 PNGDecContext *s = avctx->priv_data;
946
947 ff_thread_release_buffer(avctx, &s->last_picture);
948 av_frame_free(&s->last_picture.f);
949 ff_thread_release_buffer(avctx, &s->picture);
950 av_frame_free(&s->picture.f);
951 av_freep(&s->buffer);
952 s->buffer_size = 0;
953 av_freep(&s->last_row);
954 s->last_row_size = 0;
955 av_freep(&s->tmp_row);
956 s->tmp_row_size = 0;
957
958 return 0;
959 }
960
961 AVCodec ff_png_decoder = {
962 .name = "png",
963 .long_name = NULL_IF_CONFIG_SMALL("PNG (Portable Network Graphics) image"),
964 .type = AVMEDIA_TYPE_VIDEO,
965 .id = AV_CODEC_ID_PNG,
966 .priv_data_size = sizeof(PNGDecContext),
967 .init = png_dec_init,
968 .close = png_dec_end,
969 .decode = decode_frame,
970 .init_thread_copy = ONLY_IF_THREADS_ENABLED(png_dec_init),
971 .update_thread_context = ONLY_IF_THREADS_ENABLED(update_thread_context),
972 .capabilities = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS /*| CODEC_CAP_DRAW_HORIZ_BAND*/,
973 };
974