+++ /dev/null
-/*
- * PNG image format
- * Copyright (c) 2003 Fabrice Bellard.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- */
-#include "avformat.h"
-
-/* TODO:
- * - add 2, 4 and 16 bit depth support
- * - use filters when generating a png (better compression)
- */
-
-#ifdef CONFIG_ZLIB
-#include <zlib.h>
-
-//#define DEBUG
-
-#define PNG_COLOR_MASK_PALETTE 1
-#define PNG_COLOR_MASK_COLOR 2
-#define PNG_COLOR_MASK_ALPHA 4
-
-#define PNG_COLOR_TYPE_GRAY 0
-#define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)
-#define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR)
-#define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA)
-#define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
-
-#define PNG_FILTER_VALUE_NONE 0
-#define PNG_FILTER_VALUE_SUB 1
-#define PNG_FILTER_VALUE_UP 2
-#define PNG_FILTER_VALUE_AVG 3
-#define PNG_FILTER_VALUE_PAETH 4
-
-#define PNG_IHDR 0x0001
-#define PNG_IDAT 0x0002
-#define PNG_ALLIMAGE 0x0004
-#define PNG_PLTE 0x0008
-
-#define NB_PASSES 7
-
-#define IOBUF_SIZE 4096
-
-typedef struct PNGDecodeState {
- int state;
- int width, height;
- int bit_depth;
- int color_type;
- int compression_type;
- int interlace_type;
- int filter_type;
- int channels;
- int bits_per_pixel;
- int bpp;
-
- uint8_t *image_buf;
- int image_linesize;
- uint32_t palette[256];
- uint8_t *crow_buf;
- uint8_t *last_row;
- uint8_t *tmp_row;
- int pass;
- int crow_size; /* compressed row size (include filter type) */
- int row_size; /* decompressed row size */
- int pass_row_size; /* decompress row size of the current pass */
- int y;
- z_stream zstream;
-} PNGDecodeState;
-
-static const uint8_t pngsig[8] = {137, 80, 78, 71, 13, 10, 26, 10};
-
-/* Mask to determine which y pixels are valid in a pass */
-static const uint8_t png_pass_ymask[NB_PASSES] = {
- 0x80, 0x80, 0x08, 0x88, 0x22, 0xaa, 0x55,
-};
-
-/* Mask to determine which y pixels can be written in a pass */
-static const uint8_t png_pass_dsp_ymask[NB_PASSES] = {
- 0xff, 0xff, 0x0f, 0xcc, 0x33, 0xff, 0x55,
-};
-
-/* minimum x value */
-static const uint8_t png_pass_xmin[NB_PASSES] = {
- 0, 4, 0, 2, 0, 1, 0
-};
-
-/* x shift to get row width */
-static const uint8_t png_pass_xshift[NB_PASSES] = {
- 3, 3, 2, 2, 1, 1, 0
-};
-
-/* Mask to determine which pixels are valid in a pass */
-static const uint8_t png_pass_mask[NB_PASSES] = {
- 0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff
-};
-
-/* Mask to determine which pixels to overwrite while displaying */
-static const uint8_t png_pass_dsp_mask[NB_PASSES] = {
- 0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff
-};
-
-static int png_probe(AVProbeData *pd)
-{
- if (pd->buf_size >= 8 &&
- memcmp(pd->buf, pngsig, 8) == 0)
- return AVPROBE_SCORE_MAX;
- else
- return 0;
-}
-
-static void *png_zalloc(void *opaque, unsigned int items, unsigned int size)
-{
- return av_malloc(items * size);
-}
-
-static void png_zfree(void *opaque, void *ptr)
-{
- av_free(ptr);
-}
-
-static int png_get_nb_channels(int color_type)
-{
- int channels;
- channels = 1;
- if ((color_type & (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)) ==
- PNG_COLOR_MASK_COLOR)
- channels = 3;
- if (color_type & PNG_COLOR_MASK_ALPHA)
- channels++;
- return channels;
-}
-
-/* compute the row size of an interleaved pass */
-static int png_pass_row_size(int pass, int bits_per_pixel, int width)
-{
- int shift, xmin, pass_width;
-
- xmin = png_pass_xmin[pass];
- if (width <= xmin)
- return 0;
- shift = png_pass_xshift[pass];
- pass_width = (width - xmin + (1 << shift) - 1) >> shift;
- return (pass_width * bits_per_pixel + 7) >> 3;
-}
-
-/* NOTE: we try to construct a good looking image at each pass. width
- is the original image width. We also do pixel format convertion at
- this stage */
-static void png_put_interlaced_row(uint8_t *dst, int width,
- int bits_per_pixel, int pass,
- int color_type, const uint8_t *src)
-{
- int x, mask, dsp_mask, j, src_x, b, bpp;
- uint8_t *d;
- const uint8_t *s;
-
- mask = png_pass_mask[pass];
- dsp_mask = png_pass_dsp_mask[pass];
- switch(bits_per_pixel) {
- case 1:
- /* we must intialize the line to zero before writing to it */
- if (pass == 0)
- memset(dst, 0, (width + 7) >> 3);
- src_x = 0;
- for(x = 0; x < width; x++) {
- j = (x & 7);
- if ((dsp_mask << j) & 0x80) {
- b = (src[src_x >> 3] >> (7 - (src_x & 7))) & 1;
- dst[x >> 3] |= b << (7 - j);
- }
- if ((mask << j) & 0x80)
- src_x++;
- }
- break;
- default:
- bpp = bits_per_pixel >> 3;
- d = dst;
- s = src;
- if (color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
- for(x = 0; x < width; x++) {
- j = x & 7;
- if ((dsp_mask << j) & 0x80) {
- *(uint32_t *)d = (s[3] << 24) | (s[0] << 16) | (s[1] << 8) | s[2];
- }
- d += bpp;
- if ((mask << j) & 0x80)
- s += bpp;
- }
- } else {
- for(x = 0; x < width; x++) {
- j = x & 7;
- if ((dsp_mask << j) & 0x80) {
- memcpy(d, s, bpp);
- }
- d += bpp;
- if ((mask << j) & 0x80)
- s += bpp;
- }
- }
- break;
- }
-}
-
-static void png_get_interlaced_row(uint8_t *dst, int row_size,
- int bits_per_pixel, int pass,
- const uint8_t *src, int width)
-{
- int x, mask, dst_x, j, b, bpp;
- uint8_t *d;
- const uint8_t *s;
-
- mask = png_pass_mask[pass];
- switch(bits_per_pixel) {
- case 1:
- memset(dst, 0, row_size);
- dst_x = 0;
- for(x = 0; x < width; x++) {
- j = (x & 7);
- if ((mask << j) & 0x80) {
- b = (src[x >> 3] >> (7 - j)) & 1;
- dst[dst_x >> 3] |= b << (7 - (dst_x & 7));
- dst_x++;
- }
- }
- break;
- default:
- bpp = bits_per_pixel >> 3;
- d = dst;
- s = src;
- for(x = 0; x < width; x++) {
- j = x & 7;
- if ((mask << j) & 0x80) {
- memcpy(d, s, bpp);
- d += bpp;
- }
- s += bpp;
- }
- break;
- }
-}
-
-/* XXX: optimize */
-/* NOTE: 'dst' can be equal to 'last' */
-static void png_filter_row(uint8_t *dst, int filter_type,
- uint8_t *src, uint8_t *last, int size, int bpp)
-{
- int i, p;
-
- switch(filter_type) {
- case PNG_FILTER_VALUE_NONE:
- memcpy(dst, src, size);
- break;
- case PNG_FILTER_VALUE_SUB:
- for(i = 0; i < bpp; i++) {
- dst[i] = src[i];
- }
- for(i = bpp; i < size; i++) {
- p = dst[i - bpp];
- dst[i] = p + src[i];
- }
- break;
- case PNG_FILTER_VALUE_UP:
- for(i = 0; i < size; i++) {
- p = last[i];
- dst[i] = p + src[i];
- }
- break;
- case PNG_FILTER_VALUE_AVG:
- for(i = 0; i < bpp; i++) {
- p = (last[i] >> 1);
- dst[i] = p + src[i];
- }
- for(i = bpp; i < size; i++) {
- p = ((dst[i - bpp] + last[i]) >> 1);
- dst[i] = p + src[i];
- }
- break;
- case PNG_FILTER_VALUE_PAETH:
- for(i = 0; i < bpp; i++) {
- p = last[i];
- dst[i] = p + src[i];
- }
- for(i = bpp; i < size; i++) {
- int a, b, c, pa, pb, pc;
-
- a = dst[i - bpp];
- b = last[i];
- c = last[i - bpp];
-
- p = b - c;
- pc = a - c;
-
- pa = abs(p);
- pb = abs(pc);
- pc = abs(p + pc);
-
- if (pa <= pb && pa <= pc)
- p = a;
- else if (pb <= pc)
- p = b;
- else
- p = c;
- dst[i] = p + src[i];
- }
- break;
- }
-}
-
-static void convert_from_rgba32(uint8_t *dst, const uint8_t *src, int width)
-{
- uint8_t *d;
- int j;
- unsigned int v;
-
- d = dst;
- for(j = 0; j < width; j++) {
- v = ((uint32_t *)src)[j];
- d[0] = v >> 16;
- d[1] = v >> 8;
- d[2] = v;
- d[3] = v >> 24;
- d += 4;
- }
-}
-
-static void convert_to_rgba32(uint8_t *dst, const uint8_t *src, int width)
-{
- int j;
- unsigned int r, g, b, a;
-
- for(j = 0;j < width; j++) {
- r = src[0];
- g = src[1];
- b = src[2];
- a = src[3];
- *(uint32_t *)dst = (a << 24) | (r << 16) | (g << 8) | b;
- dst += 4;
- src += 4;
- }
-}
-
-/* process exactly one decompressed row */
-static void png_handle_row(PNGDecodeState *s)
-{
- uint8_t *ptr, *last_row;
- int got_line;
-
- if (!s->interlace_type) {
- ptr = s->image_buf + s->image_linesize * s->y;
- /* need to swap bytes correctly for RGB_ALPHA */
- if (s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
- png_filter_row(s->tmp_row, s->crow_buf[0], s->crow_buf + 1,
- s->last_row, s->row_size, s->bpp);
- memcpy(s->last_row, s->tmp_row, s->row_size);
- convert_to_rgba32(ptr, s->tmp_row, s->width);
- } else {
- /* in normal case, we avoid one copy */
- if (s->y == 0)
- last_row = s->last_row;
- else
- last_row = ptr - s->image_linesize;
-
- png_filter_row(ptr, s->crow_buf[0], s->crow_buf + 1,
- last_row, s->row_size, s->bpp);
- }
- s->y++;
- if (s->y == s->height) {
- s->state |= PNG_ALLIMAGE;
- }
- } else {
- got_line = 0;
- for(;;) {
- ptr = s->image_buf + s->image_linesize * s->y;
- if ((png_pass_ymask[s->pass] << (s->y & 7)) & 0x80) {
- /* if we already read one row, it is time to stop to
- wait for the next one */
- if (got_line)
- break;
- png_filter_row(s->tmp_row, s->crow_buf[0], s->crow_buf + 1,
- s->last_row, s->pass_row_size, s->bpp);
- memcpy(s->last_row, s->tmp_row, s->pass_row_size);
- got_line = 1;
- }
- if ((png_pass_dsp_ymask[s->pass] << (s->y & 7)) & 0x80) {
- /* NOTE: rgba32 is handled directly in png_put_interlaced_row */
- png_put_interlaced_row(ptr, s->width, s->bits_per_pixel, s->pass,
- s->color_type, s->last_row);
- }
- s->y++;
- if (s->y == s->height) {
- for(;;) {
- if (s->pass == NB_PASSES - 1) {
- s->state |= PNG_ALLIMAGE;
- goto the_end;
- } else {
- s->pass++;
- s->y = 0;
- s->pass_row_size = png_pass_row_size(s->pass,
- s->bits_per_pixel,
- s->width);
- s->crow_size = s->pass_row_size + 1;
- if (s->pass_row_size != 0)
- break;
- /* skip pass if empty row */
- }
- }
- }
- }
- the_end: ;
- }
-}
-
-static int png_decode_idat(PNGDecodeState *s, ByteIOContext *f, int length)
-{
- uint8_t buf[IOBUF_SIZE];
- int buf_size;
- int ret;
- while (length > 0) {
- /* read the buffer */
- buf_size = IOBUF_SIZE;
- if (buf_size > length)
- buf_size = length;
- ret = get_buffer(f, buf, buf_size);
- if (ret != buf_size)
- return -1;
- s->zstream.avail_in = buf_size;
- s->zstream.next_in = buf;
- /* decode one line if possible */
- while (s->zstream.avail_in > 0) {
- ret = inflate(&s->zstream, Z_PARTIAL_FLUSH);
- if (ret != Z_OK && ret != Z_STREAM_END) {
- return -1;
- }
- if (s->zstream.avail_out == 0) {
- if (!(s->state & PNG_ALLIMAGE)) {
- png_handle_row(s);
- }
- s->zstream.avail_out = s->crow_size;
- s->zstream.next_out = s->crow_buf;
- }
- }
- length -= buf_size;
- }
- return 0;
-}
-
-static int png_read(ByteIOContext *f,
- int (*alloc_cb)(void *opaque, AVImageInfo *info), void *opaque)
-{
- AVImageInfo info1, *info = &info1;
- PNGDecodeState s1, *s = &s1;
- uint32_t tag, length;
- int ret, crc;
- uint8_t buf[8];
-
- /* check signature */
- ret = get_buffer(f, buf, 8);
- if (ret != 8)
- return -1;
- if (memcmp(buf, pngsig, 8) != 0)
- return -1;
- memset(s, 0, sizeof(PNGDecodeState));
- /* init the zlib */
- s->zstream.zalloc = png_zalloc;
- s->zstream.zfree = png_zfree;
- s->zstream.opaque = NULL;
- ret = inflateInit(&s->zstream);
- if (ret != Z_OK)
- return -1;
- for(;;) {
- if (url_feof(f))
- goto fail;
- length = get_be32(f);
- if (length > 0x7fffffff)
- goto fail;
- tag = get_le32(f);
-#ifdef DEBUG
- printf("png: tag=%c%c%c%c length=%u\n",
- (tag & 0xff),
- ((tag >> 8) & 0xff),
- ((tag >> 16) & 0xff),
- ((tag >> 24) & 0xff), length);
-#endif
- switch(tag) {
- case MKTAG('I', 'H', 'D', 'R'):
- if (length != 13)
- goto fail;
- s->width = get_be32(f);
- s->height = get_be32(f);
- s->bit_depth = get_byte(f);
- s->color_type = get_byte(f);
- s->compression_type = get_byte(f);
- s->filter_type = get_byte(f);
- s->interlace_type = get_byte(f);
- crc = get_be32(f);
- s->state |= PNG_IHDR;
-#ifdef DEBUG
- printf("width=%d height=%d depth=%d color_type=%d compression_type=%d filter_type=%d interlace_type=%d\n",
- s->width, s->height, s->bit_depth, s->color_type,
- s->compression_type, s->filter_type, s->interlace_type);
-#endif
- break;
- case MKTAG('I', 'D', 'A', 'T'):
- if (!(s->state & PNG_IHDR))
- goto fail;
- if (!(s->state & PNG_IDAT)) {
- /* init image info */
- info->width = s->width;
- info->height = s->height;
- info->interleaved = (s->interlace_type != 0);
-
- s->channels = png_get_nb_channels(s->color_type);
- s->bits_per_pixel = s->bit_depth * s->channels;
- s->bpp = (s->bits_per_pixel + 7) >> 3;
- s->row_size = (info->width * s->bits_per_pixel + 7) >> 3;
-
- if (s->bit_depth == 8 &&
- s->color_type == PNG_COLOR_TYPE_RGB) {
- info->pix_fmt = PIX_FMT_RGB24;
- } else if (s->bit_depth == 8 &&
- s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
- info->pix_fmt = PIX_FMT_RGBA32;
- } else if (s->bit_depth == 8 &&
- s->color_type == PNG_COLOR_TYPE_GRAY) {
- info->pix_fmt = PIX_FMT_GRAY8;
- } else if (s->bit_depth == 1 &&
- s->color_type == PNG_COLOR_TYPE_GRAY) {
- info->pix_fmt = PIX_FMT_MONOBLACK;
- } else if (s->color_type == PNG_COLOR_TYPE_PALETTE) {
- info->pix_fmt = PIX_FMT_PAL8;
- } else {
- goto fail;
- }
- ret = alloc_cb(opaque, info);
- if (ret)
- goto the_end;
-
- /* compute the compressed row size */
- if (!s->interlace_type) {
- s->crow_size = s->row_size + 1;
- } else {
- s->pass = 0;
- s->pass_row_size = png_pass_row_size(s->pass,
- s->bits_per_pixel,
- s->width);
- s->crow_size = s->pass_row_size + 1;
- }
-#ifdef DEBUG
- printf("row_size=%d crow_size =%d\n",
- s->row_size, s->crow_size);
-#endif
- s->image_buf = info->pict.data[0];
- s->image_linesize = info->pict.linesize[0];
- /* copy the palette if needed */
- if (s->color_type == PNG_COLOR_TYPE_PALETTE)
- memcpy(info->pict.data[1], s->palette, 256 * sizeof(uint32_t));
- /* empty row is used if differencing to the first row */
- s->last_row = av_mallocz(s->row_size);
- if (!s->last_row)
- goto fail;
- if (s->interlace_type ||
- s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
- s->tmp_row = av_malloc(s->row_size);
- if (!s->tmp_row)
- goto fail;
- }
- /* compressed row */
- s->crow_buf = av_malloc(s->row_size + 1);
- if (!s->crow_buf)
- goto fail;
- s->zstream.avail_out = s->crow_size;
- s->zstream.next_out = s->crow_buf;
- }
- s->state |= PNG_IDAT;
- if (png_decode_idat(s, f, length) < 0)
- goto fail;
- /* skip crc */
- crc = get_be32(f);
- break;
- case MKTAG('P', 'L', 'T', 'E'):
- {
- int n, i, r, g, b;
-
- if ((length % 3) != 0 || length > 256 * 3)
- goto skip_tag;
- /* read the palette */
- n = length / 3;
- for(i=0;i<n;i++) {
- r = get_byte(f);
- g = get_byte(f);
- b = get_byte(f);
- s->palette[i] = (0xff << 24) | (r << 16) | (g << 8) | b;
- }
- for(;i<256;i++) {
- s->palette[i] = (0xff << 24);
- }
- s->state |= PNG_PLTE;
- crc = get_be32(f);
- }
- break;
- case MKTAG('t', 'R', 'N', 'S'):
- {
- int v, i;
-
- /* read the transparency. XXX: Only palette mode supported */
- if (s->color_type != PNG_COLOR_TYPE_PALETTE ||
- length > 256 ||
- !(s->state & PNG_PLTE))
- goto skip_tag;
- for(i=0;i<length;i++) {
- v = get_byte(f);
- s->palette[i] = (s->palette[i] & 0x00ffffff) | (v << 24);
- }
- crc = get_be32(f);
- }
- break;
- case MKTAG('I', 'E', 'N', 'D'):
- if (!(s->state & PNG_ALLIMAGE))
- goto fail;
- crc = get_be32(f);
- goto exit_loop;
- default:
- /* skip tag */
- skip_tag:
- url_fskip(f, length + 4);
- break;
- }
- }
- exit_loop:
- ret = 0;
- the_end:
- inflateEnd(&s->zstream);
- av_free(s->crow_buf);
- av_free(s->last_row);
- av_free(s->tmp_row);
- return ret;
- fail:
- ret = -1;
- goto the_end;
-}
-
-static void png_write_chunk(ByteIOContext *f, uint32_t tag,
- const uint8_t *buf, int length)
-{
- uint32_t crc;
- uint8_t tagbuf[4];
-
- put_be32(f, length);
- crc = crc32(0, Z_NULL, 0);
- tagbuf[0] = tag;
- tagbuf[1] = tag >> 8;
- tagbuf[2] = tag >> 16;
- tagbuf[3] = tag >> 24;
- crc = crc32(crc, tagbuf, 4);
- put_le32(f, tag);
- if (length > 0) {
- crc = crc32(crc, buf, length);
- put_buffer(f, buf, length);
- }
- put_be32(f, crc);
-}
-
-/* XXX: use avcodec generic function ? */
-static void to_be32(uint8_t *p, uint32_t v)
-{
- p[0] = v >> 24;
- p[1] = v >> 16;
- p[2] = v >> 8;
- p[3] = v;
-}
-
-typedef struct PNGEncodeState {
- ByteIOContext *f;
- z_stream zstream;
- uint8_t buf[IOBUF_SIZE];
-} PNGEncodeState;
-
-
-/* XXX: do filtering */
-static int png_write_row(PNGEncodeState *s, const uint8_t *data, int size)
-{
- int ret;
-
- s->zstream.avail_in = size;
- s->zstream.next_in = (uint8_t *)data;
- while (s->zstream.avail_in > 0) {
- ret = deflate(&s->zstream, Z_NO_FLUSH);
- if (ret != Z_OK)
- return -1;
- if (s->zstream.avail_out == 0) {
- png_write_chunk(s->f, MKTAG('I', 'D', 'A', 'T'), s->buf, IOBUF_SIZE);
- s->zstream.avail_out = IOBUF_SIZE;
- s->zstream.next_out = s->buf;
- }
- }
- return 0;
-}
-
-static int png_write(ByteIOContext *f, AVImageInfo *info)
-{
- PNGEncodeState s1, *s = &s1;
- int bit_depth, color_type, y, len, row_size, ret, is_progressive;
- int bits_per_pixel, pass_row_size;
- uint8_t *ptr;
- uint8_t *crow_buf = NULL;
- uint8_t *tmp_buf = NULL;
-
- s->f = f;
- is_progressive = info->interleaved;
- switch(info->pix_fmt) {
- case PIX_FMT_RGBA32:
- bit_depth = 8;
- color_type = PNG_COLOR_TYPE_RGB_ALPHA;
- break;
- case PIX_FMT_RGB24:
- bit_depth = 8;
- color_type = PNG_COLOR_TYPE_RGB;
- break;
- case PIX_FMT_GRAY8:
- bit_depth = 8;
- color_type = PNG_COLOR_TYPE_GRAY;
- break;
- case PIX_FMT_MONOBLACK:
- bit_depth = 1;
- color_type = PNG_COLOR_TYPE_GRAY;
- break;
- case PIX_FMT_PAL8:
- bit_depth = 8;
- color_type = PNG_COLOR_TYPE_PALETTE;
- break;
- default:
- return -1;
- }
- bits_per_pixel = png_get_nb_channels(color_type) * bit_depth;
- row_size = (info->width * bits_per_pixel + 7) >> 3;
-
- s->zstream.zalloc = png_zalloc;
- s->zstream.zfree = png_zfree;
- s->zstream.opaque = NULL;
- ret = deflateInit2(&s->zstream, Z_DEFAULT_COMPRESSION,
- Z_DEFLATED, 15, 8, Z_DEFAULT_STRATEGY);
- if (ret != Z_OK)
- return -1;
- crow_buf = av_malloc(row_size + 1);
- if (!crow_buf)
- goto fail;
- if (is_progressive) {
- tmp_buf = av_malloc(row_size + 1);
- if (!tmp_buf)
- goto fail;
- }
-
- /* write png header */
- put_buffer(f, pngsig, 8);
-
- to_be32(s->buf, info->width);
- to_be32(s->buf + 4, info->height);
- s->buf[8] = bit_depth;
- s->buf[9] = color_type;
- s->buf[10] = 0; /* compression type */
- s->buf[11] = 0; /* filter type */
- s->buf[12] = is_progressive; /* interlace type */
-
- png_write_chunk(f, MKTAG('I', 'H', 'D', 'R'), s->buf, 13);
-
- /* put the palette if needed */
- if (color_type == PNG_COLOR_TYPE_PALETTE) {
- int has_alpha, alpha, i;
- unsigned int v;
- uint32_t *palette;
- uint8_t *alpha_ptr;
-
- palette = (uint32_t *)info->pict.data[1];
- ptr = s->buf;
- alpha_ptr = s->buf + 256 * 3;
- has_alpha = 0;
- for(i = 0; i < 256; i++) {
- v = palette[i];
- alpha = v >> 24;
- if (alpha != 0xff)
- has_alpha = 1;
- *alpha_ptr++ = alpha;
- ptr[0] = v >> 16;
- ptr[1] = v >> 8;
- ptr[2] = v;
- ptr += 3;
- }
- png_write_chunk(f, MKTAG('P', 'L', 'T', 'E'), s->buf, 256 * 3);
- if (has_alpha) {
- png_write_chunk(f, MKTAG('t', 'R', 'N', 'S'), s->buf + 256 * 3, 256);
- }
- }
-
- /* now put each row */
- s->zstream.avail_out = IOBUF_SIZE;
- s->zstream.next_out = s->buf;
- if (is_progressive) {
- uint8_t *ptr1;
- int pass;
-
- for(pass = 0; pass < NB_PASSES; pass++) {
- /* NOTE: a pass is completely omited if no pixels would be
- output */
- pass_row_size = png_pass_row_size(pass, bits_per_pixel, info->width);
- if (pass_row_size > 0) {
- for(y = 0; y < info->height; y++) {
- if ((png_pass_ymask[pass] << (y & 7)) & 0x80) {
- ptr = info->pict.data[0] + y * info->pict.linesize[0];
- if (color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
- convert_from_rgba32(tmp_buf, ptr, info->width);
- ptr1 = tmp_buf;
- } else {
- ptr1 = ptr;
- }
- png_get_interlaced_row(crow_buf + 1, pass_row_size,
- bits_per_pixel, pass,
- ptr1, info->width);
- crow_buf[0] = PNG_FILTER_VALUE_NONE;
- png_write_row(s, crow_buf, pass_row_size + 1);
- }
- }
- }
- }
- } else {
- for(y = 0; y < info->height; y++) {
- ptr = info->pict.data[0] + y * info->pict.linesize[0];
- if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
- convert_from_rgba32(crow_buf + 1, ptr, info->width);
- else
- memcpy(crow_buf + 1, ptr, row_size);
- crow_buf[0] = PNG_FILTER_VALUE_NONE;
- png_write_row(s, crow_buf, row_size + 1);
- }
- }
- /* compress last bytes */
- for(;;) {
- ret = deflate(&s->zstream, Z_FINISH);
- if (ret == Z_OK || ret == Z_STREAM_END) {
- len = IOBUF_SIZE - s->zstream.avail_out;
- if (len > 0) {
- png_write_chunk(f, MKTAG('I', 'D', 'A', 'T'), s->buf, len);
- }
- s->zstream.avail_out = IOBUF_SIZE;
- s->zstream.next_out = s->buf;
- if (ret == Z_STREAM_END)
- break;
- } else {
- goto fail;
- }
- }
- png_write_chunk(f, MKTAG('I', 'E', 'N', 'D'), NULL, 0);
-
- put_flush_packet(f);
- ret = 0;
- the_end:
- av_free(crow_buf);
- av_free(tmp_buf);
- deflateEnd(&s->zstream);
- return ret;
- fail:
- ret = -1;
- goto the_end;
-}
-
-AVImageFormat png_image_format = {
- "png",
- "png",
- png_probe,
- png_read,
- (1 << PIX_FMT_RGBA32) | (1 << PIX_FMT_RGB24) | (1 << PIX_FMT_GRAY8) |
- (1 << PIX_FMT_MONOBLACK) | (1 << PIX_FMT_PAL8),
- png_write,
- AVIMAGE_INTERLEAVED,
-};
-#endif
projects / synfig.git / blobdiff