pngdec.c File Reference
#include "libavutil/imgutils.h"
#include "avcodec.h"
#include "bytestream.h"
#include "png.h"
#include "dsputil.h"
#include <zlib.h>

Go to the source code of this file.

Data Structures

struct  PNGDecContext

Macros

#define UNROLL1(bpp, op)
#define UNROLL_FILTER(op)
#define OP_SUB(x, s, l)   x+s
#define OP_AVG(x, s, l)   (((x + l) >> 1) + s) & 0xff

Typedefs

typedef struct PNGDecContext PNGDecContext

Functions

static void png_put_interlaced_row (uint8_t *dst, int width, int bits_per_pixel, int pass, int color_type, const uint8_t *src)
void ff_add_png_paeth_prediction (uint8_t *dst, uint8_t *src, uint8_t *top, int w, int bpp)
static void png_filter_row (DSPContext *dsp, uint8_t *dst, int filter_type, uint8_t *src, uint8_t *last, int size, int bpp)
static av_always_inline void convert_to_rgb32_loco (uint8_t *dst, const uint8_t *src, int width, int loco)
static void convert_to_rgb32 (uint8_t *dst, const uint8_t *src, int width, int loco)
static void deloco_rgb24 (uint8_t *dst, int size)
static void png_handle_row (PNGDecContext *s)
static int png_decode_idat (PNGDecContext *s, int length)
static int decode_frame (AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)
static av_cold int png_dec_init (AVCodecContext *avctx)
static av_cold int png_dec_end (AVCodecContext *avctx)

Variables

static const uint8_t png_pass_dsp_ymask [NB_PASSES]
static const uint8_t png_pass_dsp_mask [NB_PASSES]
AVCodec ff_png_decoder

Macro Definition Documentation

#define OP_AVG (   x,
  s,
 
)    (((x + l) >> 1) + s) & 0xff
#define OP_SUB (   x,
  s,
 
)    x+s

Referenced by png_filter_row().

#define UNROLL1 (   bpp,
  op 
)
Value:
{\
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]);\
}\
}

Definition at line 162 of file pngdec.c.

#define UNROLL_FILTER (   op)
Value:
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)\
else {\
for (; i < size; i += bpp) {\
int j;\
for (j = 0; j < bpp; j++)\
dst[i+j] = op(dst[i+j-bpp], src[i+j], last[i+j]);\
}\
}

Definition at line 178 of file pngdec.c.

Referenced by png_filter_row().

Typedef Documentation

typedef struct PNGDecContext PNGDecContext

Function Documentation

static void convert_to_rgb32 ( uint8_t *  dst,
const uint8_t *  src,
int  width,
int  loco 
)
static

Definition at line 264 of file pngdec.c.

Referenced by png_handle_row().

static av_always_inline void convert_to_rgb32_loco ( uint8_t *  dst,
const uint8_t *  src,
int  width,
int  loco 
)
static

Definition at line 244 of file pngdec.c.

Referenced by convert_to_rgb32().

static int decode_frame ( AVCodecContext avctx,
void data,
int *  data_size,
AVPacket avpkt 
)
static

Definition at line 388 of file pngdec.c.

static void deloco_rgb24 ( uint8_t *  dst,
int  size 
)
static

Definition at line 272 of file pngdec.c.

Referenced by png_handle_row().

void ff_add_png_paeth_prediction ( uint8_t *  dst,
uint8_t *  src,
uint8_t *  top,
int  w,
int  bpp 
)

Definition at line 135 of file pngdec.c.

Referenced by dsputil_init(), and png_filter_row().

static av_cold int png_dec_end ( AVCodecContext avctx)
static

Definition at line 644 of file pngdec.c.

static av_cold int png_dec_init ( AVCodecContext avctx)
static

Definition at line 632 of file pngdec.c.

static int png_decode_idat ( PNGDecContext s,
int  length 
)
static

Definition at line 360 of file pngdec.c.

Referenced by decode_frame().

static void png_filter_row ( DSPContext dsp,
uint8_t *  dst,
int  filter_type,
uint8_t *  src,
uint8_t *  last,
int  size,
int  bpp 
)
static

Definition at line 192 of file pngdec.c.

Referenced by png_handle_row().

static void png_handle_row ( PNGDecContext s)
static

Definition at line 283 of file pngdec.c.

Referenced by png_decode_idat().

static void png_put_interlaced_row ( uint8_t *  dst,
int  width,
int  bits_per_pixel,
int  pass,
int  color_type,
const uint8_t *  src 
)
static

Definition at line 80 of file pngdec.c.

Referenced by png_handle_row().

Variable Documentation

AVCodec ff_png_decoder
Initial value:
{
.name = "png",
.id = CODEC_ID_PNG,
.priv_data_size = sizeof(PNGDecContext),
.capabilities = CODEC_CAP_DR1 ,
.long_name = NULL_IF_CONFIG_SMALL("PNG image"),
}

Definition at line 656 of file pngdec.c.

const uint8_t png_pass_dsp_mask[NB_PASSES]
static
Initial value:
{
0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff
}

Definition at line 73 of file pngdec.c.

Referenced by png_put_interlaced_row().

const uint8_t png_pass_dsp_ymask[NB_PASSES]
static
Initial value:
{
0xff, 0xff, 0x0f, 0xcc, 0x33, 0xff, 0x55,
}

Definition at line 68 of file pngdec.c.

Referenced by png_handle_row().