3 * Copyright (c) 2003 Fabrice Bellard
5 * This file is part of FFmpeg.
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.
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.
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
24 #include "libavutil/bprint.h"
25 #include "libavutil/imgutils.h"
27 #include "bytestream.h"
35 typedef struct PNGDecContext {
37 AVCodecContext *avctx;
40 ThreadFrame last_picture;
56 uint32_t palette[256];
59 unsigned int last_row_size;
61 unsigned int tmp_row_size;
65 int crow_size; /* compressed row size (include filter type) */
66 int row_size; /* decompressed row size */
67 int pass_row_size; /* decompress row size of the current pass */
72 /* Mask to determine which pixels are valid in a pass */
73 static const uint8_t png_pass_mask[NB_PASSES] = {
74 0x01, 0x01, 0x11, 0x11, 0x55, 0x55, 0xff,
77 /* Mask to determine which y pixels can be written in a pass */
78 static const uint8_t png_pass_dsp_ymask[NB_PASSES] = {
79 0xff, 0xff, 0x0f, 0xff, 0x33, 0xff, 0x55,
82 /* Mask to determine which pixels to overwrite while displaying */
83 static const uint8_t png_pass_dsp_mask[NB_PASSES] = {
84 0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff
87 /* NOTE: we try to construct a good looking image at each pass. width
88 * is the original image width. We also do pixel format conversion at
90 static void png_put_interlaced_row(uint8_t *dst, int width,
91 int bits_per_pixel, int pass,
92 int color_type, const uint8_t *src)
94 int x, mask, dsp_mask, j, src_x, b, bpp;
98 mask = png_pass_mask[pass];
99 dsp_mask = png_pass_dsp_mask[pass];
101 switch (bits_per_pixel) {
104 for (x = 0; x < width; x++) {
106 if ((dsp_mask << j) & 0x80) {
107 b = (src[src_x >> 3] >> (7 - (src_x & 7))) & 1;
108 dst[x >> 3] &= 0xFF7F>>j;
109 dst[x >> 3] |= b << (7 - j);
111 if ((mask << j) & 0x80)
117 for (x = 0; x < width; x++) {
118 int j2 = 2 * (x & 3);
120 if ((dsp_mask << j) & 0x80) {
121 b = (src[src_x >> 2] >> (6 - 2*(src_x & 3))) & 3;
122 dst[x >> 2] &= 0xFF3F>>j2;
123 dst[x >> 2] |= b << (6 - j2);
125 if ((mask << j) & 0x80)
131 for (x = 0; x < width; x++) {
134 if ((dsp_mask << j) & 0x80) {
135 b = (src[src_x >> 1] >> (4 - 4*(src_x & 1))) & 15;
136 dst[x >> 1] &= 0xFF0F>>j2;
137 dst[x >> 1] |= b << (4 - j2);
139 if ((mask << j) & 0x80)
144 bpp = bits_per_pixel >> 3;
147 for (x = 0; x < width; x++) {
149 if ((dsp_mask << j) & 0x80) {
153 if ((mask << j) & 0x80)
160 void ff_add_png_paeth_prediction(uint8_t *dst, uint8_t *src, uint8_t *top,
164 for (i = 0; i < w; i++) {
165 int a, b, c, p, pa, pb, pc;
178 if (pa <= pb && pa <= pc)
188 #define UNROLL1(bpp, op) \
197 for (; i <= size - bpp; i += bpp) { \
198 dst[i + 0] = r = op(r, src[i + 0], last[i + 0]); \
201 dst[i + 1] = g = op(g, src[i + 1], last[i + 1]); \
204 dst[i + 2] = b = op(b, src[i + 2], last[i + 2]); \
207 dst[i + 3] = a = op(a, src[i + 3], last[i + 3]); \
211 #define UNROLL_FILTER(op) \
214 } else if (bpp == 2) { \
216 } else if (bpp == 3) { \
218 } else if (bpp == 4) { \
221 for (; i < size; i++) { \
222 dst[i] = op(dst[i - bpp], src[i], last[i]); \
225 /* NOTE: 'dst' can be equal to 'last' */
226 static void png_filter_row(PNGDSPContext *dsp, uint8_t *dst, int filter_type,
227 uint8_t *src, uint8_t *last, int size, int bpp)
229 int i, p, r, g, b, a;
231 switch (filter_type) {
232 case PNG_FILTER_VALUE_NONE:
233 memcpy(dst, src, size);
235 case PNG_FILTER_VALUE_SUB:
236 for (i = 0; i < bpp; i++)
240 for (; i < size; i += bpp) {
241 unsigned s = *(int *)(src + i);
242 p = ((s & 0x7f7f7f7f) + (p & 0x7f7f7f7f)) ^ ((s ^ p) & 0x80808080);
243 *(int *)(dst + i) = p;
246 #define OP_SUB(x, s, l) ((x) + (s))
247 UNROLL_FILTER(OP_SUB);
250 case PNG_FILTER_VALUE_UP:
251 dsp->add_bytes_l2(dst, src, last, size);
253 case PNG_FILTER_VALUE_AVG:
254 for (i = 0; i < bpp; i++) {
258 #define OP_AVG(x, s, l) (((((x) + (l)) >> 1) + (s)) & 0xff)
259 UNROLL_FILTER(OP_AVG);
261 case PNG_FILTER_VALUE_PAETH:
262 for (i = 0; i < bpp; i++) {
266 if (bpp > 2 && size > 4) {
267 /* would write off the end of the array if we let it process
268 * the last pixel with bpp=3 */
269 int w = bpp == 4 ? size : size - 3;
270 dsp->add_paeth_prediction(dst + i, src + i, last + i, w - i, bpp);
273 ff_add_png_paeth_prediction(dst + i, src + i, last + i, size - i, bpp);
278 /* This used to be called "deloco" in FFmpeg
279 * and is actually an inverse reversible colorspace transformation */
280 #define YUV2RGB(NAME, TYPE) \
281 static void deloco_ ## NAME(TYPE *dst, int size, int alpha) \
284 for (i = 0; i < size; i += 3 + alpha) { \
285 int g = dst [i + 1]; \
291 YUV2RGB(rgb8, uint8_t)
292 YUV2RGB(rgb16, uint16_t)
294 /* process exactly one decompressed row */
295 static void png_handle_row(PNGDecContext *s)
297 uint8_t *ptr, *last_row;
300 if (!s->interlace_type) {
301 ptr = s->image_buf + s->image_linesize * s->y;
303 last_row = s->last_row;
305 last_row = ptr - s->image_linesize;
307 png_filter_row(&s->dsp, ptr, s->crow_buf[0], s->crow_buf + 1,
308 last_row, s->row_size, s->bpp);
309 /* loco lags by 1 row so that it doesn't interfere with top prediction */
310 if (s->filter_type == PNG_FILTER_TYPE_LOCO && s->y > 0) {
311 if (s->bit_depth == 16) {
312 deloco_rgb16((uint16_t *)(ptr - s->image_linesize), s->row_size / 2,
313 s->color_type == PNG_COLOR_TYPE_RGB_ALPHA);
315 deloco_rgb8(ptr - s->image_linesize, s->row_size,
316 s->color_type == PNG_COLOR_TYPE_RGB_ALPHA);
320 if (s->y == s->height) {
321 s->state |= PNG_ALLIMAGE;
322 if (s->filter_type == PNG_FILTER_TYPE_LOCO) {
323 if (s->bit_depth == 16) {
324 deloco_rgb16((uint16_t *)ptr, s->row_size / 2,
325 s->color_type == PNG_COLOR_TYPE_RGB_ALPHA);
327 deloco_rgb8(ptr, s->row_size,
328 s->color_type == PNG_COLOR_TYPE_RGB_ALPHA);
335 ptr = s->image_buf + s->image_linesize * s->y;
336 if ((ff_png_pass_ymask[s->pass] << (s->y & 7)) & 0x80) {
337 /* if we already read one row, it is time to stop to
338 * wait for the next one */
341 png_filter_row(&s->dsp, s->tmp_row, s->crow_buf[0], s->crow_buf + 1,
342 s->last_row, s->pass_row_size, s->bpp);
343 FFSWAP(uint8_t *, s->last_row, s->tmp_row);
344 FFSWAP(unsigned int, s->last_row_size, s->tmp_row_size);
347 if ((png_pass_dsp_ymask[s->pass] << (s->y & 7)) & 0x80) {
348 png_put_interlaced_row(ptr, s->width, s->bits_per_pixel, s->pass,
349 s->color_type, s->last_row);
352 if (s->y == s->height) {
353 memset(s->last_row, 0, s->row_size);
355 if (s->pass == NB_PASSES - 1) {
356 s->state |= PNG_ALLIMAGE;
361 s->pass_row_size = ff_png_pass_row_size(s->pass,
364 s->crow_size = s->pass_row_size + 1;
365 if (s->pass_row_size != 0)
367 /* skip pass if empty row */
376 static int png_decode_idat(PNGDecContext *s, int length)
379 s->zstream.avail_in = FFMIN(length, bytestream2_get_bytes_left(&s->gb));
380 s->zstream.next_in = (unsigned char *)s->gb.buffer;
381 bytestream2_skip(&s->gb, length);
383 /* decode one line if possible */
384 while (s->zstream.avail_in > 0) {
385 ret = inflate(&s->zstream, Z_PARTIAL_FLUSH);
386 if (ret != Z_OK && ret != Z_STREAM_END) {
387 av_log(s->avctx, AV_LOG_ERROR, "inflate returned error %d\n", ret);
388 return AVERROR_EXTERNAL;
390 if (s->zstream.avail_out == 0) {
391 if (!(s->state & PNG_ALLIMAGE)) {
394 s->zstream.avail_out = s->crow_size;
395 s->zstream.next_out = s->crow_buf;
397 if (ret == Z_STREAM_END && s->zstream.avail_in > 0) {
398 av_log(NULL, AV_LOG_WARNING,
399 "%d undecompressed bytes left in buffer\n", s->zstream.avail_in);
406 static int decode_zbuf(AVBPrint *bp, const uint8_t *data,
407 const uint8_t *data_end)
414 zstream.zalloc = ff_png_zalloc;
415 zstream.zfree = ff_png_zfree;
416 zstream.opaque = NULL;
417 if (inflateInit(&zstream) != Z_OK)
418 return AVERROR_EXTERNAL;
419 zstream.next_in = (unsigned char *)data;
420 zstream.avail_in = data_end - data;
421 av_bprint_init(bp, 0, -1);
423 while (zstream.avail_in > 0) {
424 av_bprint_get_buffer(bp, 1, &buf, &buf_size);
426 ret = AVERROR(ENOMEM);
429 zstream.next_out = buf;
430 zstream.avail_out = buf_size;
431 ret = inflate(&zstream, Z_PARTIAL_FLUSH);
432 if (ret != Z_OK && ret != Z_STREAM_END) {
433 ret = AVERROR_EXTERNAL;
436 bp->len += zstream.next_out - buf;
437 if (ret == Z_STREAM_END)
440 inflateEnd(&zstream);
441 bp->str[bp->len] = 0;
445 inflateEnd(&zstream);
446 av_bprint_finalize(bp, NULL);
450 static uint8_t *iso88591_to_utf8(const uint8_t *in, size_t size_in)
455 for (i = 0; i < size_in; i++)
456 extra += in[i] >= 0x80;
457 if (size_in == SIZE_MAX || extra > SIZE_MAX - size_in - 1)
459 q = out = av_malloc(size_in + extra + 1);
462 for (i = 0; i < size_in; i++) {
464 *(q++) = 0xC0 | (in[i] >> 6);
465 *(q++) = 0x80 | (in[i] & 0x3F);
474 static int decode_text_chunk(PNGDecContext *s, uint32_t length, int compressed,
478 const uint8_t *data = s->gb.buffer;
479 const uint8_t *data_end = data + length;
480 const uint8_t *keyword = data;
481 const uint8_t *keyword_end = memchr(keyword, 0, data_end - keyword);
482 uint8_t *kw_utf8 = NULL, *text, *txt_utf8 = NULL;
487 return AVERROR_INVALIDDATA;
488 data = keyword_end + 1;
491 if (data == data_end)
492 return AVERROR_INVALIDDATA;
495 return AVERROR_INVALIDDATA;
496 if ((ret = decode_zbuf(&bp, data, data_end)) < 0)
499 av_bprint_finalize(&bp, (char **)&text);
501 return AVERROR(ENOMEM);
503 text = (uint8_t *)data;
504 text_len = data_end - text;
507 kw_utf8 = iso88591_to_utf8(keyword, keyword_end - keyword);
508 txt_utf8 = iso88591_to_utf8(text, text_len);
511 if (!(kw_utf8 && txt_utf8)) {
514 return AVERROR(ENOMEM);
517 av_dict_set(dict, kw_utf8, txt_utf8,
518 AV_DICT_DONT_STRDUP_KEY | AV_DICT_DONT_STRDUP_VAL);
522 static int decode_ihdr_chunk(AVCodecContext *avctx, PNGDecContext *s,
526 return AVERROR_INVALIDDATA;
527 s->width = bytestream2_get_be32(&s->gb);
528 s->height = bytestream2_get_be32(&s->gb);
529 if (av_image_check_size(s->width, s->height, 0, avctx)) {
530 s->width = s->height = 0;
531 av_log(avctx, AV_LOG_ERROR, "Invalid image size\n");
532 return AVERROR_INVALIDDATA;
534 s->bit_depth = bytestream2_get_byte(&s->gb);
535 s->color_type = bytestream2_get_byte(&s->gb);
536 s->compression_type = bytestream2_get_byte(&s->gb);
537 s->filter_type = bytestream2_get_byte(&s->gb);
538 s->interlace_type = bytestream2_get_byte(&s->gb);
539 bytestream2_skip(&s->gb, 4); /* crc */
540 s->state |= PNG_IHDR;
541 if (avctx->debug & FF_DEBUG_PICT_INFO)
542 av_log(avctx, AV_LOG_DEBUG, "width=%d height=%d depth=%d color_type=%d "
543 "compression_type=%d filter_type=%d interlace_type=%d\n",
544 s->width, s->height, s->bit_depth, s->color_type,
545 s->compression_type, s->filter_type, s->interlace_type);
550 static int decode_phys_chunk(AVCodecContext *avctx, PNGDecContext *s)
552 if (s->state & PNG_IDAT) {
553 av_log(avctx, AV_LOG_ERROR, "pHYs after IDAT\n");
554 return AVERROR_INVALIDDATA;
556 avctx->sample_aspect_ratio.num = bytestream2_get_be32(&s->gb);
557 avctx->sample_aspect_ratio.den = bytestream2_get_be32(&s->gb);
558 if (avctx->sample_aspect_ratio.num < 0 || avctx->sample_aspect_ratio.den < 0)
559 avctx->sample_aspect_ratio = (AVRational){ 0, 1 };
560 bytestream2_skip(&s->gb, 1); /* unit specifier */
561 bytestream2_skip(&s->gb, 4); /* crc */
566 static int decode_idat_chunk(AVCodecContext *avctx, PNGDecContext *s,
567 uint32_t length, AVFrame *p)
571 if (!(s->state & PNG_IHDR)) {
572 av_log(avctx, AV_LOG_ERROR, "IDAT without IHDR\n");
573 return AVERROR_INVALIDDATA;
575 if (!(s->state & PNG_IDAT)) {
576 /* init image info */
577 avctx->width = s->width;
578 avctx->height = s->height;
580 s->channels = ff_png_get_nb_channels(s->color_type);
581 s->bits_per_pixel = s->bit_depth * s->channels;
582 s->bpp = (s->bits_per_pixel + 7) >> 3;
583 s->row_size = (avctx->width * s->bits_per_pixel + 7) >> 3;
585 if ((s->bit_depth == 2 || s->bit_depth == 4 || s->bit_depth == 8) &&
586 s->color_type == PNG_COLOR_TYPE_RGB) {
587 avctx->pix_fmt = AV_PIX_FMT_RGB24;
588 } else if ((s->bit_depth == 2 || s->bit_depth == 4 || s->bit_depth == 8) &&
589 s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
590 avctx->pix_fmt = AV_PIX_FMT_RGBA;
591 } else if ((s->bit_depth == 2 || s->bit_depth == 4 || s->bit_depth == 8) &&
592 s->color_type == PNG_COLOR_TYPE_GRAY) {
593 avctx->pix_fmt = AV_PIX_FMT_GRAY8;
594 } else if (s->bit_depth == 16 &&
595 s->color_type == PNG_COLOR_TYPE_GRAY) {
596 avctx->pix_fmt = AV_PIX_FMT_GRAY16BE;
597 } else if (s->bit_depth == 16 &&
598 s->color_type == PNG_COLOR_TYPE_RGB) {
599 avctx->pix_fmt = AV_PIX_FMT_RGB48BE;
600 } else if (s->bit_depth == 16 &&
601 s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
602 avctx->pix_fmt = AV_PIX_FMT_RGBA64BE;
603 } else if ((s->bits_per_pixel == 1 || s->bits_per_pixel == 2 || s->bits_per_pixel == 4 || s->bits_per_pixel == 8) &&
604 s->color_type == PNG_COLOR_TYPE_PALETTE) {
605 avctx->pix_fmt = AV_PIX_FMT_PAL8;
606 } else if (s->bit_depth == 1 && s->bits_per_pixel == 1) {
607 avctx->pix_fmt = AV_PIX_FMT_MONOBLACK;
608 } else if (s->bit_depth == 8 &&
609 s->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) {
610 avctx->pix_fmt = AV_PIX_FMT_YA8;
611 } else if (s->bit_depth == 16 &&
612 s->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) {
613 avctx->pix_fmt = AV_PIX_FMT_YA16BE;
615 av_log(avctx, AV_LOG_ERROR, "unsupported bit depth %d "
616 "and color type %d\n",
617 s->bit_depth, s->color_type);
618 return AVERROR_INVALIDDATA;
621 if ((ret = ff_thread_get_buffer(avctx, &s->picture, AV_GET_BUFFER_FLAG_REF)) < 0)
623 ff_thread_finish_setup(avctx);
625 p->pict_type = AV_PICTURE_TYPE_I;
627 p->interlaced_frame = !!s->interlace_type;
629 /* compute the compressed row size */
630 if (!s->interlace_type) {
631 s->crow_size = s->row_size + 1;
634 s->pass_row_size = ff_png_pass_row_size(s->pass,
637 s->crow_size = s->pass_row_size + 1;
639 av_dlog(avctx, "row_size=%d crow_size =%d\n",
640 s->row_size, s->crow_size);
641 s->image_buf = p->data[0];
642 s->image_linesize = p->linesize[0];
643 /* copy the palette if needed */
644 if (avctx->pix_fmt == AV_PIX_FMT_PAL8)
645 memcpy(p->data[1], s->palette, 256 * sizeof(uint32_t));
646 /* empty row is used if differencing to the first row */
647 av_fast_padded_mallocz(&s->last_row, &s->last_row_size, s->row_size);
649 return AVERROR_INVALIDDATA;
650 if (s->interlace_type ||
651 s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
652 av_fast_padded_malloc(&s->tmp_row, &s->tmp_row_size, s->row_size);
654 return AVERROR_INVALIDDATA;
657 av_fast_padded_malloc(&s->buffer, &s->buffer_size, s->row_size + 16);
659 return AVERROR(ENOMEM);
661 /* we want crow_buf+1 to be 16-byte aligned */
662 s->crow_buf = s->buffer + 15;
663 s->zstream.avail_out = s->crow_size;
664 s->zstream.next_out = s->crow_buf;
666 s->state |= PNG_IDAT;
667 if ((ret = png_decode_idat(s, length)) < 0)
669 bytestream2_skip(&s->gb, 4); /* crc */
674 static int decode_plte_chunk(AVCodecContext *avctx, PNGDecContext *s,
679 if ((length % 3) != 0 || length > 256 * 3)
680 return AVERROR_INVALIDDATA;
681 /* read the palette */
683 for (i = 0; i < n; i++) {
684 r = bytestream2_get_byte(&s->gb);
685 g = bytestream2_get_byte(&s->gb);
686 b = bytestream2_get_byte(&s->gb);
687 s->palette[i] = (0xFFU << 24) | (r << 16) | (g << 8) | b;
690 s->palette[i] = (0xFFU << 24);
691 s->state |= PNG_PLTE;
692 bytestream2_skip(&s->gb, 4); /* crc */
697 static int decode_trns_chunk(AVCodecContext *avctx, PNGDecContext *s,
702 /* read the transparency. XXX: Only palette mode supported */
703 if (s->color_type != PNG_COLOR_TYPE_PALETTE ||
705 !(s->state & PNG_PLTE))
706 return AVERROR_INVALIDDATA;
707 for (i = 0; i < length; i++) {
708 v = bytestream2_get_byte(&s->gb);
709 s->palette[i] = (s->palette[i] & 0x00ffffff) | (v << 24);
711 bytestream2_skip(&s->gb, 4); /* crc */
716 static void handle_small_bpp(PNGDecContext *s, AVFrame *p)
718 if (s->bits_per_pixel == 1 && s->color_type == PNG_COLOR_TYPE_PALETTE) {
720 uint8_t *pd = p->data[0];
721 for (j = 0; j < s->height; j++) {
723 for (k = 7; k >= 1; k--)
724 if ((s->width&7) >= k)
725 pd[8*i + k - 1] = (pd[i]>>8-k) & 1;
726 for (i--; i >= 0; i--) {
727 pd[8*i + 7]= pd[i] & 1;
728 pd[8*i + 6]= (pd[i]>>1) & 1;
729 pd[8*i + 5]= (pd[i]>>2) & 1;
730 pd[8*i + 4]= (pd[i]>>3) & 1;
731 pd[8*i + 3]= (pd[i]>>4) & 1;
732 pd[8*i + 2]= (pd[i]>>5) & 1;
733 pd[8*i + 1]= (pd[i]>>6) & 1;
734 pd[8*i + 0]= pd[i]>>7;
736 pd += s->image_linesize;
738 } else if (s->bits_per_pixel == 2) {
740 uint8_t *pd = p->data[0];
741 for (j = 0; j < s->height; j++) {
743 if (s->color_type == PNG_COLOR_TYPE_PALETTE) {
744 if ((s->width&3) >= 3) pd[4*i + 2]= (pd[i] >> 2) & 3;
745 if ((s->width&3) >= 2) pd[4*i + 1]= (pd[i] >> 4) & 3;
746 if ((s->width&3) >= 1) pd[4*i + 0]= pd[i] >> 6;
747 for (i--; i >= 0; i--) {
748 pd[4*i + 3]= pd[i] & 3;
749 pd[4*i + 2]= (pd[i]>>2) & 3;
750 pd[4*i + 1]= (pd[i]>>4) & 3;
751 pd[4*i + 0]= pd[i]>>6;
754 if ((s->width&3) >= 3) pd[4*i + 2]= ((pd[i]>>2) & 3)*0x55;
755 if ((s->width&3) >= 2) pd[4*i + 1]= ((pd[i]>>4) & 3)*0x55;
756 if ((s->width&3) >= 1) pd[4*i + 0]= ( pd[i]>>6 )*0x55;
757 for (i--; i >= 0; i--) {
758 pd[4*i + 3]= ( pd[i] & 3)*0x55;
759 pd[4*i + 2]= ((pd[i]>>2) & 3)*0x55;
760 pd[4*i + 1]= ((pd[i]>>4) & 3)*0x55;
761 pd[4*i + 0]= ( pd[i]>>6 )*0x55;
764 pd += s->image_linesize;
766 } else if (s->bits_per_pixel == 4) {
768 uint8_t *pd = p->data[0];
769 for (j = 0; j < s->height; j++) {
771 if (s->color_type == PNG_COLOR_TYPE_PALETTE) {
772 if (s->width&1) pd[2*i+0]= pd[i]>>4;
773 for (i--; i >= 0; i--) {
774 pd[2*i + 1] = pd[i] & 15;
775 pd[2*i + 0] = pd[i] >> 4;
778 if (s->width & 1) pd[2*i + 0]= (pd[i] >> 4) * 0x11;
779 for (i--; i >= 0; i--) {
780 pd[2*i + 1] = (pd[i] & 15) * 0x11;
781 pd[2*i + 0] = (pd[i] >> 4) * 0x11;
784 pd += s->image_linesize;
789 static int decode_fctl_chunk(AVCodecContext *avctx, PNGDecContext *s,
792 uint32_t sequence_number, width, height, x_offset, y_offset;
795 return AVERROR_INVALIDDATA;
797 sequence_number = bytestream2_get_be32(&s->gb);
798 width = bytestream2_get_be32(&s->gb);
799 height = bytestream2_get_be32(&s->gb);
800 x_offset = bytestream2_get_be32(&s->gb);
801 y_offset = bytestream2_get_be32(&s->gb);
802 bytestream2_skip(&s->gb, 10); /* delay_num (2)
809 if (width != s->width || height != s->height ||
810 x_offset != 0 || y_offset != 0) {
811 if (sequence_number == 0)
812 return AVERROR_INVALIDDATA;
813 avpriv_request_sample(avctx, "non key frames");
814 return AVERROR_PATCHWELCOME;
820 static int decode_frame_common(AVCodecContext *avctx, PNGDecContext *s,
821 AVFrame *p, AVPacket *avpkt)
823 AVDictionary *metadata = NULL;
824 uint32_t tag, length;
825 int decode_next_dat = 0;
826 int ret = AVERROR_INVALIDDATA;
829 length = bytestream2_get_bytes_left(&s->gb);
831 if (avctx->codec_id == AV_CODEC_ID_APNG && length == 0) {
832 if (!(s->state & PNG_IDAT))
837 av_log(avctx, AV_LOG_ERROR, "%d bytes left\n", length);
838 if ( s->state & PNG_ALLIMAGE
839 && avctx->strict_std_compliance <= FF_COMPLIANCE_NORMAL)
844 length = bytestream2_get_be32(&s->gb);
845 if (length > 0x7fffffff || length > bytestream2_get_bytes_left(&s->gb)) {
846 av_log(avctx, AV_LOG_ERROR, "chunk too big\n");
849 tag = bytestream2_get_le32(&s->gb);
850 if (avctx->debug & FF_DEBUG_STARTCODE)
851 av_log(avctx, AV_LOG_DEBUG, "png: tag=%c%c%c%c length=%u\n",
854 ((tag >> 16) & 0xff),
855 ((tag >> 24) & 0xff), length);
857 case MKTAG('I', 'H', 'D', 'R'):
858 if (decode_ihdr_chunk(avctx, s, length) < 0)
861 case MKTAG('p', 'H', 'Y', 's'):
862 if (decode_phys_chunk(avctx, s) < 0)
865 case MKTAG('f', 'c', 'T', 'L'):
866 if (avctx->codec_id != AV_CODEC_ID_APNG)
868 if ((ret = decode_fctl_chunk(avctx, s, length)) < 0)
872 case MKTAG('f', 'd', 'A', 'T'):
873 if (avctx->codec_id != AV_CODEC_ID_APNG)
875 if (!decode_next_dat)
877 bytestream2_get_be32(&s->gb);
880 case MKTAG('I', 'D', 'A', 'T'):
881 if (avctx->codec_id == AV_CODEC_ID_APNG && !decode_next_dat)
883 if (decode_idat_chunk(avctx, s, length, p) < 0)
886 case MKTAG('P', 'L', 'T', 'E'):
887 if (decode_plte_chunk(avctx, s, length) < 0)
890 case MKTAG('t', 'R', 'N', 'S'):
891 if (decode_trns_chunk(avctx, s, length) < 0)
894 case MKTAG('t', 'E', 'X', 't'):
895 if (decode_text_chunk(s, length, 0, &metadata) < 0)
896 av_log(avctx, AV_LOG_WARNING, "Broken tEXt chunk\n");
897 bytestream2_skip(&s->gb, length + 4);
899 case MKTAG('z', 'T', 'X', 't'):
900 if (decode_text_chunk(s, length, 1, &metadata) < 0)
901 av_log(avctx, AV_LOG_WARNING, "Broken zTXt chunk\n");
902 bytestream2_skip(&s->gb, length + 4);
904 case MKTAG('I', 'E', 'N', 'D'):
905 if (!(s->state & PNG_ALLIMAGE))
906 av_log(avctx, AV_LOG_ERROR, "IEND without all image\n");
907 if (!(s->state & (PNG_ALLIMAGE|PNG_IDAT))) {
910 bytestream2_skip(&s->gb, 4); /* crc */
915 bytestream2_skip(&s->gb, length + 4);
921 if (s->bits_per_pixel <= 4)
922 handle_small_bpp(s, p);
924 /* handle p-frames only if a predecessor frame is available */
925 if (s->last_picture.f->data[0]) {
926 if ( !(avpkt->flags & AV_PKT_FLAG_KEY) && avctx->codec_tag != AV_RL32("MPNG")
927 && s->last_picture.f->width == p->width
928 && s->last_picture.f->height== p->height
929 && s->last_picture.f->format== p->format
932 uint8_t *pd = p->data[0];
933 uint8_t *pd_last = s->last_picture.f->data[0];
934 int ls = FFMIN(av_image_get_linesize(p->format, s->width, 0), s->width * s->bpp);
936 ff_thread_await_progress(&s->last_picture, INT_MAX, 0);
937 for (j = 0; j < s->height; j++) {
938 for (i = 0; i < ls; i++)
940 pd += s->image_linesize;
941 pd_last += s->image_linesize;
945 ff_thread_report_progress(&s->picture, INT_MAX, 0);
947 av_frame_set_metadata(p, metadata);
952 av_dict_free(&metadata);
953 ff_thread_report_progress(&s->picture, INT_MAX, 0);
957 #if CONFIG_PNG_DECODER
958 static int decode_frame_png(AVCodecContext *avctx,
959 void *data, int *got_frame,
962 PNGDecContext *const s = avctx->priv_data;
963 const uint8_t *buf = avpkt->data;
964 int buf_size = avpkt->size;
969 ff_thread_release_buffer(avctx, &s->last_picture);
970 FFSWAP(ThreadFrame, s->picture, s->last_picture);
973 bytestream2_init(&s->gb, buf, buf_size);
975 /* check signature */
976 sig = bytestream2_get_be64(&s->gb);
979 av_log(avctx, AV_LOG_ERROR, "Missing png signature\n");
980 return AVERROR_INVALIDDATA;
986 s->zstream.zalloc = ff_png_zalloc;
987 s->zstream.zfree = ff_png_zfree;
988 s->zstream.opaque = NULL;
989 ret = inflateInit(&s->zstream);
991 av_log(avctx, AV_LOG_ERROR, "inflateInit returned error %d\n", ret);
992 return AVERROR_EXTERNAL;
995 if ((ret = decode_frame_common(avctx, s, p, avpkt)) < 0)
998 if ((ret = av_frame_ref(data, s->picture.f)) < 0)
1003 ret = bytestream2_tell(&s->gb);
1005 inflateEnd(&s->zstream);
1011 #if CONFIG_APNG_DECODER
1012 static int decode_frame_apng(AVCodecContext *avctx,
1013 void *data, int *got_frame,
1016 PNGDecContext *const s = avctx->priv_data;
1020 ff_thread_release_buffer(avctx, &s->last_picture);
1021 FFSWAP(ThreadFrame, s->picture, s->last_picture);
1024 if (!(s->state & PNG_IHDR)) {
1025 if (!avctx->extradata_size)
1026 return AVERROR_INVALIDDATA;
1028 /* only init fields, there is no zlib use in extradata */
1029 s->zstream.zalloc = ff_png_zalloc;
1030 s->zstream.zfree = ff_png_zfree;
1032 bytestream2_init(&s->gb, avctx->extradata, avctx->extradata_size);
1033 if ((ret = decode_frame_common(avctx, s, p, avpkt)) < 0)
1037 /* reset state for a new frame */
1038 if ((ret = inflateInit(&s->zstream)) != Z_OK) {
1039 av_log(avctx, AV_LOG_ERROR, "inflateInit returned error %d\n", ret);
1040 ret = AVERROR_EXTERNAL;
1044 s->state &= ~(PNG_IDAT | PNG_ALLIMAGE);
1045 bytestream2_init(&s->gb, avpkt->data, avpkt->size);
1046 if ((ret = decode_frame_common(avctx, s, p, avpkt)) < 0)
1049 if (!(s->state & PNG_ALLIMAGE))
1050 av_log(avctx, AV_LOG_WARNING, "Frame did not contain a complete image\n");
1051 if (!(s->state & (PNG_ALLIMAGE|PNG_IDAT))) {
1052 ret = AVERROR_INVALIDDATA;
1055 if ((ret = av_frame_ref(data, s->picture.f)) < 0)
1059 ret = bytestream2_tell(&s->gb);
1062 inflateEnd(&s->zstream);
1067 static int update_thread_context(AVCodecContext *dst, const AVCodecContext *src)
1069 PNGDecContext *psrc = src->priv_data;
1070 PNGDecContext *pdst = dst->priv_data;
1075 ff_thread_release_buffer(dst, &pdst->picture);
1076 if (psrc->picture.f->data[0])
1077 return ff_thread_ref_frame(&pdst->picture, &psrc->picture);
1082 static av_cold int png_dec_init(AVCodecContext *avctx)
1084 PNGDecContext *s = avctx->priv_data;
1087 s->last_picture.f = av_frame_alloc();
1088 s->picture.f = av_frame_alloc();
1089 if (!s->last_picture.f || !s->picture.f)
1090 return AVERROR(ENOMEM);
1092 if (!avctx->internal->is_copy) {
1093 avctx->internal->allocate_progress = 1;
1094 ff_pngdsp_init(&s->dsp);
1100 static av_cold int png_dec_end(AVCodecContext *avctx)
1102 PNGDecContext *s = avctx->priv_data;
1104 ff_thread_release_buffer(avctx, &s->last_picture);
1105 av_frame_free(&s->last_picture.f);
1106 ff_thread_release_buffer(avctx, &s->picture);
1107 av_frame_free(&s->picture.f);
1108 av_freep(&s->buffer);
1110 av_freep(&s->last_row);
1111 s->last_row_size = 0;
1112 av_freep(&s->tmp_row);
1113 s->tmp_row_size = 0;
1118 #if CONFIG_APNG_DECODER
1119 AVCodec ff_apng_decoder = {
1121 .long_name = NULL_IF_CONFIG_SMALL("APNG (Animated Portable Network Graphics) image"),
1122 .type = AVMEDIA_TYPE_VIDEO,
1123 .id = AV_CODEC_ID_APNG,
1124 .priv_data_size = sizeof(PNGDecContext),
1125 .init = png_dec_init,
1126 .close = png_dec_end,
1127 .decode = decode_frame_apng,
1128 .init_thread_copy = ONLY_IF_THREADS_ENABLED(png_dec_init),
1129 .update_thread_context = ONLY_IF_THREADS_ENABLED(update_thread_context),
1130 .capabilities = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS /*| CODEC_CAP_DRAW_HORIZ_BAND*/,
1134 #if CONFIG_PNG_DECODER
1135 AVCodec ff_png_decoder = {
1137 .long_name = NULL_IF_CONFIG_SMALL("PNG (Portable Network Graphics) image"),
1138 .type = AVMEDIA_TYPE_VIDEO,
1139 .id = AV_CODEC_ID_PNG,
1140 .priv_data_size = sizeof(PNGDecContext),
1141 .init = png_dec_init,
1142 .close = png_dec_end,
1143 .decode = decode_frame_png,
1144 .init_thread_copy = ONLY_IF_THREADS_ENABLED(png_dec_init),
1145 .update_thread_context = ONLY_IF_THREADS_ENABLED(update_thread_context),
1146 .capabilities = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS /*| CODEC_CAP_DRAW_HORIZ_BAND*/,