diff options
Diffstat (limited to 'ffmpeg1/libavcodec/pngenc.c')
| -rw-r--r-- | ffmpeg1/libavcodec/pngenc.c | 480 |
1 files changed, 480 insertions, 0 deletions
diff --git a/ffmpeg1/libavcodec/pngenc.c b/ffmpeg1/libavcodec/pngenc.c new file mode 100644 index 0000000..a401c78 --- /dev/null +++ b/ffmpeg1/libavcodec/pngenc.c @@ -0,0 +1,480 @@ +/* + * 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 "internal.h" +#include "bytestream.h" +#include "dsputil.h" +#include "png.h" + +#include "libavutil/avassert.h" + +/* TODO: + * - add 2, 4 and 16 bit depth support + */ + +#include <zlib.h> + +//#define DEBUG + +#define IOBUF_SIZE 4096 + +typedef struct PNGEncContext { + DSPContext dsp; + + uint8_t *bytestream; + uint8_t *bytestream_start; + uint8_t *bytestream_end; + AVFrame picture; + + int filter_type; + + z_stream zstream; + uint8_t buf[IOBUF_SIZE]; +} PNGEncContext; + +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 = (int[]){0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff}[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 sub_png_paeth_prediction(uint8_t *dst, uint8_t *src, uint8_t *top, int w, int bpp) +{ + int i; + for(i = 0; i < w; i++) { + int a, b, c, p, pa, pb, pc; + + a = src[i - bpp]; + b = top[i]; + c = top[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] = src[i] - p; + } +} + +static void png_filter_row(DSPContext *dsp, uint8_t *dst, int filter_type, + uint8_t *src, uint8_t *top, int size, int bpp) +{ + int i; + + switch(filter_type) { + case PNG_FILTER_VALUE_NONE: + memcpy(dst, src, size); + break; + case PNG_FILTER_VALUE_SUB: + dsp->diff_bytes(dst, src, src-bpp, size); + memcpy(dst, src, bpp); + break; + case PNG_FILTER_VALUE_UP: + dsp->diff_bytes(dst, src, top, size); + break; + case PNG_FILTER_VALUE_AVG: + for(i = 0; i < bpp; i++) + dst[i] = src[i] - (top[i] >> 1); + for(; i < size; i++) + dst[i] = src[i] - ((src[i-bpp] + top[i]) >> 1); + break; + case PNG_FILTER_VALUE_PAETH: + for(i = 0; i < bpp; i++) + dst[i] = src[i] - top[i]; + sub_png_paeth_prediction(dst+i, src+i, top+i, size-i, bpp); + break; + } +} + +static uint8_t *png_choose_filter(PNGEncContext *s, uint8_t *dst, + uint8_t *src, uint8_t *top, int size, int bpp) +{ + int pred = s->filter_type; + av_assert0(bpp || !pred); + if(!top && pred) + pred = PNG_FILTER_VALUE_SUB; + if(pred == PNG_FILTER_VALUE_MIXED) { + int i; + int cost, bcost = INT_MAX; + uint8_t *buf1 = dst, *buf2 = dst + size + 16; + for(pred=0; pred<5; pred++) { + png_filter_row(&s->dsp, buf1+1, pred, src, top, size, bpp); + buf1[0] = pred; + cost = 0; + for(i=0; i<=size; i++) + cost += abs((int8_t)buf1[i]); + if(cost < bcost) { + bcost = cost; + FFSWAP(uint8_t*, buf1, buf2); + } + } + return buf2; + } else { + png_filter_row(&s->dsp, dst+1, pred, src, top, size, bpp); + dst[0] = pred; + return dst; + } +} + +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, av_bswap32(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(PNGEncContext *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, AVPacket *pkt, + const AVFrame *pict, int *got_packet) +{ + PNGEncContext *s = avctx->priv_data; + AVFrame * const p= &s->picture; + int bit_depth, color_type, y, len, row_size, ret, is_progressive; + int bits_per_pixel, pass_row_size, enc_row_size; + int64_t max_packet_size; + int compression_level; + uint8_t *ptr, *top; + uint8_t *crow_base = NULL, *crow_buf, *crow; + uint8_t *progressive_buf = NULL; + uint8_t *top_buf = NULL; + + *p = *pict; + p->pict_type= AV_PICTURE_TYPE_I; + p->key_frame= 1; + + is_progressive = !!(avctx->flags & CODEC_FLAG_INTERLACED_DCT); + switch(avctx->pix_fmt) { + case AV_PIX_FMT_RGBA64BE: + bit_depth = 16; + color_type = PNG_COLOR_TYPE_RGB_ALPHA; + break; + case AV_PIX_FMT_RGB48BE: + bit_depth = 16; + color_type = PNG_COLOR_TYPE_RGB; + break; + case AV_PIX_FMT_RGBA: + bit_depth = 8; + color_type = PNG_COLOR_TYPE_RGB_ALPHA; + break; + case AV_PIX_FMT_RGB24: + bit_depth = 8; + color_type = PNG_COLOR_TYPE_RGB; + break; + case AV_PIX_FMT_GRAY16BE: + bit_depth = 16; + color_type = PNG_COLOR_TYPE_GRAY; + break; + case AV_PIX_FMT_GRAY8: + bit_depth = 8; + color_type = PNG_COLOR_TYPE_GRAY; + break; + case AV_PIX_FMT_GRAY8A: + bit_depth = 8; + color_type = PNG_COLOR_TYPE_GRAY_ALPHA; + break; + case AV_PIX_FMT_MONOBLACK: + bit_depth = 1; + color_type = PNG_COLOR_TYPE_GRAY; + break; + case AV_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; + compression_level = avctx->compression_level == FF_COMPRESSION_DEFAULT ? + Z_DEFAULT_COMPRESSION : + av_clip(avctx->compression_level, 0, 9); + ret = deflateInit2(&s->zstream, compression_level, + Z_DEFLATED, 15, 8, Z_DEFAULT_STRATEGY); + if (ret != Z_OK) + return -1; + + enc_row_size = deflateBound(&s->zstream, row_size); + max_packet_size = avctx->height * (int64_t)(enc_row_size + + ((enc_row_size + IOBUF_SIZE - 1) / IOBUF_SIZE) * 12) + + FF_MIN_BUFFER_SIZE; + if (max_packet_size > INT_MAX) + return AVERROR(ENOMEM); + if ((ret = ff_alloc_packet2(avctx, pkt, max_packet_size)) < 0) + return ret; + + s->bytestream_start = + s->bytestream = pkt->data; + s->bytestream_end = pkt->data + pkt->size; + + crow_base = av_malloc((row_size + 32) << (s->filter_type == PNG_FILTER_VALUE_MIXED)); + if (!crow_base) + goto fail; + crow_buf = crow_base + 15; // pixel data should be aligned, but there's a control byte before it + if (is_progressive) { + progressive_buf = av_malloc(row_size + 1); + if (!progressive_buf) + goto fail; + } + if (is_progressive) { + top_buf = av_malloc(row_size + 1); + if (!top_buf) + goto fail; + } + + /* write png header */ + AV_WB64(s->bytestream, PNGSIG); + 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); + + AV_WB32(s->buf, avctx->sample_aspect_ratio.num); + AV_WB32(s->buf + 4, avctx->sample_aspect_ratio.den); + s->buf[8] = 0; /* unit specifier is unknown */ + png_write_chunk(&s->bytestream, MKTAG('p', 'H', 'Y', 's'), s->buf, 9); + + /* 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; + 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) { + int pass; + + for(pass = 0; pass < NB_PASSES; pass++) { + /* NOTE: a pass is completely omitted 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) { + top = NULL; + for(y = 0; y < avctx->height; y++) { + if ((ff_png_pass_ymask[pass] << (y & 7)) & 0x80) { + ptr = p->data[0] + y * p->linesize[0]; + FFSWAP(uint8_t*, progressive_buf, top_buf); + png_get_interlaced_row(progressive_buf, pass_row_size, + bits_per_pixel, pass, + ptr, avctx->width); + crow = png_choose_filter(s, crow_buf, progressive_buf, top, pass_row_size, bits_per_pixel>>3); + png_write_row(s, crow, pass_row_size + 1); + top = progressive_buf; + } + } + } + } + } else { + top = NULL; + for(y = 0; y < avctx->height; y++) { + ptr = p->data[0] + y * p->linesize[0]; + crow = png_choose_filter(s, crow_buf, ptr, top, row_size, bits_per_pixel>>3); + png_write_row(s, crow, row_size + 1); + top = ptr; + } + } + /* 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); + + pkt->size = s->bytestream - s->bytestream_start; + pkt->flags |= AV_PKT_FLAG_KEY; + *got_packet = 1; + ret = 0; + + the_end: + av_free(crow_base); + av_free(progressive_buf); + av_free(top_buf); + deflateEnd(&s->zstream); + return ret; + fail: + ret = -1; + goto the_end; +} + +static av_cold int png_enc_init(AVCodecContext *avctx){ + PNGEncContext *s = avctx->priv_data; + + switch(avctx->pix_fmt) { + case AV_PIX_FMT_RGBA: + avctx->bits_per_coded_sample = 32; + break; + case AV_PIX_FMT_RGB24: + avctx->bits_per_coded_sample = 24; + break; + case AV_PIX_FMT_GRAY8: + avctx->bits_per_coded_sample = 0x28; + break; + case AV_PIX_FMT_MONOBLACK: + avctx->bits_per_coded_sample = 1; + break; + case AV_PIX_FMT_PAL8: + avctx->bits_per_coded_sample = 8; + } + + avcodec_get_frame_defaults(&s->picture); + avctx->coded_frame= &s->picture; + ff_dsputil_init(&s->dsp, avctx); + + s->filter_type = av_clip(avctx->prediction_method, PNG_FILTER_VALUE_NONE, PNG_FILTER_VALUE_MIXED); + if(avctx->pix_fmt == AV_PIX_FMT_MONOBLACK) + s->filter_type = PNG_FILTER_VALUE_NONE; + + return 0; +} + +AVCodec ff_png_encoder = { + .name = "png", + .type = AVMEDIA_TYPE_VIDEO, + .id = AV_CODEC_ID_PNG, + .priv_data_size = sizeof(PNGEncContext), + .init = png_enc_init, + .encode2 = encode_frame, + .capabilities = CODEC_CAP_FRAME_THREADS | CODEC_CAP_INTRA_ONLY, + .pix_fmts = (const enum AVPixelFormat[]){ + AV_PIX_FMT_RGB24, AV_PIX_FMT_RGBA, + AV_PIX_FMT_RGB48BE, AV_PIX_FMT_RGBA64BE, + AV_PIX_FMT_PAL8, + AV_PIX_FMT_GRAY8, AV_PIX_FMT_GRAY8A, + AV_PIX_FMT_GRAY16BE, + AV_PIX_FMT_MONOBLACK, AV_PIX_FMT_NONE + }, + .long_name = NULL_IF_CONFIG_SMALL("PNG (Portable Network Graphics) image"), +}; 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