| /* |
| * 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 = ((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 |
