From b958a7f1114a49b0a0e36479ba96c83c4fe4c3b3 Mon Sep 17 00:00:00 2001 From: Måns Rullgård Date: Sun, 15 Jul 2007 18:24:26 +0000 Subject: separate en/decoder specific parts from png.c Originally committed as revision 9686 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/pngenc.c | 309 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 309 insertions(+) create mode 100644 libavcodec/pngenc.c (limited to 'libavcodec/pngenc.c') diff --git a/libavcodec/pngenc.c b/libavcodec/pngenc.c new file mode 100644 index 0000000000..d4cd6deae3 --- /dev/null +++ b/libavcodec/pngenc.c @@ -0,0 +1,309 @@ +/* + * PNG image format + * Copyright (c) 2003 Fabrice Bellard. + * + * This file is part of FFmpeg. + * + * FFmpeg 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 2.1 of the License, or (at your option) any later version. + * + * FFmpeg 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 FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ +#include "avcodec.h" +#include "bytestream.h" +#include "png.h" + +/* TODO: + * - add 2, 4 and 16 bit depth support + * - use filters when generating a png (better compression) + */ + +#include + +//#define DEBUG + +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 = ff_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; + } +} + +static void convert_from_rgb32(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 png_write_chunk(uint8_t **f, uint32_t tag, + const uint8_t *buf, int length) +{ + uint32_t crc; + uint8_t tagbuf[4]; + + bytestream_put_be32(f, length); + crc = crc32(0, Z_NULL, 0); + AV_WL32(tagbuf, tag); + crc = crc32(crc, tagbuf, 4); + bytestream_put_be32(f, bswap_32(tag)); + if (length > 0) { + crc = crc32(crc, buf, length); + memcpy(*f, buf, length); + *f += length; + } + bytestream_put_be32(f, crc); +} + +/* 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 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_RGB32: + 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 = ff_png_get_nb_channels(color_type) * bit_depth; + row_size = (avctx->width * bits_per_pixel + 7) >> 3; + + s->zstream.zalloc = ff_png_zalloc; + s->zstream.zfree = ff_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, ff_pngsig, 8); + s->bytestream += 8; + + AV_WB32(s->buf, avctx->width); + AV_WB32(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 && alpha != 0xff) + has_alpha = 1; + *alpha_ptr++ = alpha; + bytestream_put_be24(&ptr, v); + } + 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 = ff_png_pass_row_size(pass, bits_per_pixel, avctx->width); + if (pass_row_size > 0) { + for(y = 0; y < avctx->height; y++) { + if ((ff_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_rgb32(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_rgb32(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_encoder = { + "png", + CODEC_TYPE_VIDEO, + CODEC_ID_PNG, + sizeof(PNGContext), + ff_png_common_init, + encode_frame, + NULL, //encode_end, + .pix_fmts= (enum PixelFormat[]){PIX_FMT_RGB24, PIX_FMT_RGB32, PIX_FMT_PAL8, PIX_FMT_GRAY8, PIX_FMT_MONOBLACK, -1}, +}; 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