diff options
Diffstat (limited to 'contrib/ffmpeg/libavcodec/pngdec.c')
| -rw-r--r-- | contrib/ffmpeg/libavcodec/pngdec.c | 621 |
1 files changed, 621 insertions, 0 deletions
diff --git a/contrib/ffmpeg/libavcodec/pngdec.c b/contrib/ffmpeg/libavcodec/pngdec.c new file mode 100644 index 000000000..90dac4dfa --- /dev/null +++ b/contrib/ffmpeg/libavcodec/pngdec.c @@ -0,0 +1,621 @@ +/* + * 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" +#include "dsputil.h" + +/* TODO: + * - add 2, 4 and 16 bit depth support + */ + +#include <zlib.h> + +//#define DEBUG + +typedef struct PNGDecContext { + DSPContext dsp; + + const uint8_t *bytestream; + const uint8_t *bytestream_start; + const 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; +} PNGDecContext; + +/* 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, +}; + +/* 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 +}; + +/* NOTE: we try to construct a good looking image at each pass. width + is the original image width. We also do pixel format conversion 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 = ff_png_pass_mask[pass]; + dsp_mask = png_pass_dsp_mask[pass]; + switch(bits_per_pixel) { + case 1: + /* we must initialize 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; + } +} + +void ff_add_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 = dst[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] = p + src[i]; + } +} + +#define UNROLL1(bpp, op) {\ + r = dst[0];\ + if(bpp >= 2) g = dst[1];\ + if(bpp >= 3) b = dst[2];\ + if(bpp >= 4) a = dst[3];\ + for(; i < size; i+=bpp) {\ + dst[i+0] = r = op(r, src[i+0], last[i+0]);\ + if(bpp == 1) continue;\ + dst[i+1] = g = op(g, src[i+1], last[i+1]);\ + if(bpp == 2) continue;\ + dst[i+2] = b = op(b, src[i+2], last[i+2]);\ + if(bpp == 3) continue;\ + dst[i+3] = a = op(a, src[i+3], last[i+3]);\ + }\ +} + +#define UNROLL_FILTER(op)\ + if(bpp == 1) UNROLL1(1, op)\ + else if(bpp == 2) UNROLL1(2, op)\ + else if(bpp == 3) UNROLL1(3, op)\ + else if(bpp == 4) UNROLL1(4, op)\ + +/* NOTE: 'dst' can be equal to 'last' */ +static void png_filter_row(DSPContext *dsp, uint8_t *dst, int filter_type, + uint8_t *src, uint8_t *last, int size, int bpp) +{ + int i, p, r, g, b, a; + + 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]; + } + if(bpp == 4) { + p = *(int*)dst; + for(; i < size; i+=bpp) { + int s = *(int*)(src+i); + p = ((s&0x7f7f7f7f) + (p&0x7f7f7f7f)) ^ ((s^p)&0x80808080); + *(int*)(dst+i) = p; + } + } else { +#define OP_SUB(x,s,l) x+s + UNROLL_FILTER(OP_SUB); + } + break; + case PNG_FILTER_VALUE_UP: + dsp->add_bytes_l2(dst, src, last, size); + break; + case PNG_FILTER_VALUE_AVG: + for(i = 0; i < bpp; i++) { + p = (last[i] >> 1); + dst[i] = p + src[i]; + } +#define OP_AVG(x,s,l) (((x + l) >> 1) + s) & 0xff + UNROLL_FILTER(OP_AVG); + break; + case PNG_FILTER_VALUE_PAETH: + for(i = 0; i < bpp; i++) { + p = last[i]; + dst[i] = p + src[i]; + } + if(bpp > 1 && size > 4) { + // would write off the end of the array if we let it process the last pixel with bpp=3 + int w = bpp==4 ? size : size-3; + dsp->add_png_paeth_prediction(dst+i, src+i, last+i, w-i, bpp); + i = w; + } + ff_add_png_paeth_prediction(dst+i, src+i, last+i, size-i, bpp); + break; + } +} + +static av_always_inline void convert_to_rgb32_loco(uint8_t *dst, const uint8_t *src, int width, int loco) +{ + 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]; + if(loco) { + r = (r+g)&0xff; + b = (b+g)&0xff; + } + *(uint32_t *)dst = (a << 24) | (r << 16) | (g << 8) | b; + dst += 4; + src += 4; + } +} + +static void convert_to_rgb32(uint8_t *dst, const uint8_t *src, int width, int loco) +{ + if(loco) + convert_to_rgb32_loco(dst, src, width, 1); + else + convert_to_rgb32_loco(dst, src, width, 0); +} + +static void deloco_rgb24(uint8_t *dst, int size) +{ + int i; + for(i=0; i<size; i+=3) { + int g = dst[i+1]; + dst[i+0] += g; + dst[i+2] += g; + } +} + +/* process exactly one decompressed row */ +static void png_handle_row(PNGDecContext *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->dsp, s->tmp_row, s->crow_buf[0], s->crow_buf + 1, + s->last_row, s->row_size, s->bpp); + convert_to_rgb32(ptr, s->tmp_row, s->width, s->filter_type == PNG_FILTER_TYPE_LOCO); + FFSWAP(uint8_t*, s->last_row, s->tmp_row); + } 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(&s->dsp, ptr, s->crow_buf[0], s->crow_buf + 1, + last_row, s->row_size, s->bpp); + } + /* loco lags by 1 row so that it doesn't interfere with top prediction */ + if (s->filter_type == PNG_FILTER_TYPE_LOCO && + s->color_type == PNG_COLOR_TYPE_RGB && s->y > 0) + deloco_rgb24(ptr - s->image_linesize, s->row_size); + s->y++; + if (s->y == s->height) { + s->state |= PNG_ALLIMAGE; + if (s->filter_type == PNG_FILTER_TYPE_LOCO && + s->color_type == PNG_COLOR_TYPE_RGB) + deloco_rgb24(ptr, s->row_size); + } + } else { + got_line = 0; + for(;;) { + ptr = s->image_buf + s->image_linesize * s->y; + if ((ff_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->dsp, s->tmp_row, s->crow_buf[0], s->crow_buf + 1, + s->last_row, s->pass_row_size, s->bpp); + FFSWAP(uint8_t*, s->last_row, s->tmp_row); + got_line = 1; + } + if ((png_pass_dsp_ymask[s->pass] << (s->y & 7)) & 0x80) { + /* NOTE: RGB32 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 = ff_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(PNGDecContext *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, + const uint8_t *buf, int buf_size) +{ + PNGDecContext * 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, ff_pngsig, 8) != 0 && + memcmp(s->bytestream, ff_mngsig, 8) != 0) + return -1; + s->bytestream+= 8; + s->y= + s->state=0; +// memset(s, 0, sizeof(PNGDecContext)); + /* init the zlib */ + s->zstream.zalloc = ff_png_zalloc; + s->zstream.zfree = ff_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 = bytestream_get_be32(&s->bytestream); + if (length > 0x7fffffff) + goto fail; + tag32 = bytestream_get_be32(&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 = bytestream_get_be32(&s->bytestream); + s->height = bytestream_get_be32(&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 = bytestream_get_be32(&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 = ff_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_RGB32; + } else if (s->bit_depth == 8 && + s->color_type == PNG_COLOR_TYPE_GRAY) { + avctx->pix_fmt = PIX_FMT_GRAY8; + } else if (s->bit_depth == 16 && + s->color_type == PNG_COLOR_TYPE_GRAY) { + avctx->pix_fmt = PIX_FMT_GRAY16BE; + } 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 = ff_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 = bytestream_get_be32(&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 = bytestream_get_be32(&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 = bytestream_get_be32(&s->bytestream); + } + break; + case MKTAG('I', 'E', 'N', 'D'): + if (!(s->state & PNG_ALLIMAGE)) + goto fail; + crc = bytestream_get_be32(&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 int png_dec_init(AVCodecContext *avctx){ + PNGDecContext *s = avctx->priv_data; + + avcodec_get_frame_defaults((AVFrame*)&s->picture); + avctx->coded_frame= (AVFrame*)&s->picture; + dsputil_init(&s->dsp, avctx); + + return 0; +} + +AVCodec png_decoder = { + "png", + CODEC_TYPE_VIDEO, + CODEC_ID_PNG, + sizeof(PNGDecContext), + png_dec_init, + NULL, + NULL, //decode_end, + decode_frame, + 0 /*CODEC_CAP_DR1*/ /*| CODEC_CAP_DRAW_HORIZ_BAND*/, + NULL +}; |