/* * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "avcodec.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 PNGContext { uint8_t *bytestream; uint8_t *bytestream_start; uint8_t *bytestream_end; AVFrame picture; 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; uint8_t buf[IOBUF_SIZE]; } PNGContext; static unsigned int get32(uint8_t **b){ (*b) += 4; return ((*b)[-4]<<24) + ((*b)[-3]<<16) + ((*b)[-2]<<8) + (*b)[-1]; } static void put32(uint8_t **b, unsigned int v){ *(*b)++= v>>24; *(*b)++= v>>16; *(*b)++= v>>8; *(*b)++= v; } 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 }; #if 0 static int png_probe(AVProbeData *pd) { if (pd->buf_size >= 8 && memcmp(pd->buf, pngsig, 8) == 0) return AVPROBE_SCORE_MAX; else return 0; } #endif static void *png_zalloc(void *opaque, unsigned int items, unsigned int size) { if(items >= UINT_MAX / size) return NULL; 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 = ((const 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(PNGContext *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(PNGContext *s, int length) { int ret; s->zstream.avail_in = length; s->zstream.next_in = s->bytestream; s->bytestream += length; if(s->bytestream > s->bytestream_end) return -1; /* 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; } } return 0; } static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8_t *buf, int buf_size) { PNGContext * const s = avctx->priv_data; AVFrame *picture = data; AVFrame * const p= (AVFrame*)&s->picture; uint32_t tag, length; int ret, crc; s->bytestream_start= s->bytestream= buf; s->bytestream_end= buf + buf_size; /* check signature */ if (memcmp(s->bytestream, pngsig, 8) != 0) return -1; s->bytestream+= 8; s->y= s->state=0; // memset(s, 0, sizeof(PNGContext)); /* 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(;;) { int tag32; if (s->bytestream >= s->bytestream_end) goto fail; length = get32(&s->bytestream); if (length > 0x7fffffff) goto fail; tag32 = get32(&s->bytestream); tag = bswap_32(tag32); #ifdef DEBUG av_log(avctx, AV_LOG_DEBUG, "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 = get32(&s->bytestream); s->height = get32(&s->bytestream); if(avcodec_check_dimensions(avctx, s->width, s->height)){ s->width= s->height= 0; goto fail; } s->bit_depth = *s->bytestream++; s->color_type = *s->bytestream++; s->compression_type = *s->bytestream++; s->filter_type = *s->bytestream++; s->interlace_type = *s->bytestream++; crc = get32(&s->bytestream); s->state |= PNG_IHDR; #ifdef DEBUG av_log(avctx, AV_LOG_DEBUG, "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 */ avctx->width = s->width; avctx->height = s->height; 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 = (avctx->width * s->bits_per_pixel + 7) >> 3; if (s->bit_depth == 8 && s->color_type == PNG_COLOR_TYPE_RGB) { avctx->pix_fmt = PIX_FMT_RGB24; } else if (s->bit_depth == 8 && s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) { avctx->pix_fmt = PIX_FMT_RGBA32; } else if (s->bit_depth == 8 && s->color_type == PNG_COLOR_TYPE_GRAY) { avctx->pix_fmt = PIX_FMT_GRAY8; } else if (s->bit_depth == 1 && s->color_type == PNG_COLOR_TYPE_GRAY) { avctx->pix_fmt = PIX_FMT_MONOBLACK; } else if (s->color_type == PNG_COLOR_TYPE_PALETTE) { avctx->pix_fmt = PIX_FMT_PAL8; } else { goto fail; } if(p->data[0]) avctx->release_buffer(avctx, p); p->reference= 0; if(avctx->get_buffer(avctx, p) < 0){ av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); goto fail; } p->pict_type= FF_I_TYPE; p->key_frame= 1; p->interlaced_frame = !!s->interlace_type; /* 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 av_log(avctx, AV_LOG_DEBUG, "row_size=%d crow_size =%d\n", s->row_size, s->crow_size); #endif s->image_buf = p->data[0]; s->image_linesize = p->linesize[0]; /* copy the palette if needed */ if (s->color_type == PNG_COLOR_TYPE_PALETTE) memcpy(p->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, length) < 0) goto fail; /* skip crc */ crc = get32(&s->bytestream); 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 = *s->bytestream++; g = *s->bytestream++; b = *s->bytestream++; s->palette[i] = (0xff << 24) | (r << 16) | (g << 8) | b; } for(;i<256;i++) { s->palette[i] = (0xff << 24); } s->state |= PNG_PLTE; crc = get32(&s->bytestream); } 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 = *s->bytestream++; s->palette[i] = (s->palette[i] & 0x00ffffff) | (v << 24); } crc = get32(&s->bytestream); } break; case MKTAG('I', 'E', 'N', 'D'): if (!(s->state & PNG_ALLIMAGE)) goto fail; crc = get32(&s->bytestream); goto exit_loop; default: /* skip tag */ skip_tag: s->bytestream += length + 4; break; } } exit_loop: *picture= *(AVFrame*)&s->picture; *data_size = sizeof(AVPicture); ret = s->bytestream - s->bytestream_start; the_end: inflateEnd(&s->zstream); av_freep(&s->crow_buf); av_freep(&s->last_row); av_freep(&s->tmp_row); return ret; fail: ret = -1; goto the_end; } static void png_write_chunk(uint8_t **f, uint32_t tag, const uint8_t *buf, int length) { uint32_t crc; uint8_t tagbuf[4]; put32(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); put32(f, bswap_32(tag)); if (length > 0) { crc = crc32(crc, buf, length); memcpy(*f, buf, length); *f += length; } put32(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; } /* XXX: do filtering */ static int png_write_row(PNGContext *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) { if(s->bytestream_end - s->bytestream > IOBUF_SIZE + 100) png_write_chunk(&s->bytestream, 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 common_init(AVCodecContext *avctx){ PNGContext *s = avctx->priv_data; avcodec_get_frame_defaults((AVFrame*)&s->picture); avctx->coded_frame= (AVFrame*)&s->picture; // s->avctx= avctx; return 0; } static int encode_frame(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){ PNGContext *s = avctx->priv_data; AVFrame *pict = data; AVFrame * const p= (AVFrame*)&s->picture; 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; *p = *pict; p->pict_type= FF_I_TYPE; p->key_frame= 1; s->bytestream_start= s->bytestream= buf; s->bytestream_end= buf+buf_size; is_progressive = !!(avctx->flags & CODEC_FLAG_INTERLACED_DCT); switch(avctx->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 = (avctx->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 */ memcpy(s->bytestream, pngsig, 8); s->bytestream += 8; to_be32(s->buf, avctx->width); to_be32(s->buf + 4, avctx->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(&s->bytestream, 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 *)p->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(&s->bytestream, MKTAG('P', 'L', 'T', 'E'), s->buf, 256 * 3); if (has_alpha) { png_write_chunk(&s->bytestream, 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, avctx->width); if (pass_row_size > 0) { for(y = 0; y < avctx->height; y++) { if ((png_pass_ymask[pass] << (y & 7)) & 0x80) { ptr = p->data[0] + y * p->linesize[0]; if (color_type == PNG_COLOR_TYPE_RGB_ALPHA) { convert_from_rgba32(tmp_buf, ptr, avctx->width); ptr1 = tmp_buf; } else { ptr1 = ptr; } png_get_interlaced_row(crow_buf + 1, pass_row_size, bits_per_pixel, pass, ptr1, avctx->width); crow_buf[0] = PNG_FILTER_VALUE_NONE; png_write_row(s, crow_buf, pass_row_size + 1); } } } } } else { for(y = 0; y < avctx->height; y++) { ptr = p->data[0] + y * p->linesize[0]; if (color_type == PNG_COLOR_TYPE_RGB_ALPHA) convert_from_rgba32(crow_buf + 1, ptr, avctx->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 && s->bytestream_end - s->bytestream > len + 100) { png_write_chunk(&s->bytestream, 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(&s->bytestream, MKTAG('I', 'E', 'N', 'D'), NULL, 0); ret = s->bytestream - s->bytestream_start; the_end: av_free(crow_buf); av_free(tmp_buf); deflateEnd(&s->zstream); return ret; fail: ret = -1; goto the_end; } AVCodec png_decoder = { "png", CODEC_TYPE_VIDEO, CODEC_ID_PNG, sizeof(PNGContext), common_init, NULL, NULL, //decode_end, decode_frame, 0 /*CODEC_CAP_DR1*/ /*| CODEC_CAP_DRAW_HORIZ_BAND*/, NULL }; #ifdef CONFIG_PNG_ENCODER AVCodec png_encoder = { "png", CODEC_TYPE_VIDEO, CODEC_ID_PNG, sizeof(PNGContext), common_init, encode_frame, NULL, //encode_end, .pix_fmts= (enum PixelFormat[]){PIX_FMT_RGB24, PIX_FMT_RGBA32, PIX_FMT_PAL8, PIX_FMT_GRAY8, PIX_FMT_MONOBLACK, -1}, }; #endif // CONFIG_PNG_ENCODER #endif