pngdec.c File Reference

#include "libavutil/bprint.h"
#include "libavutil/imgutils.h"
#include "avcodec.h"
#include "bytestream.h"
#include "internal.h"
#include "png.h"
#include "pngdsp.h"
#include "thread.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
#define	YUV2RGB(NAME, TYPE)

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 (PNGDSPContext *dsp, uint8_t *dst, int filter_type, uint8_t *src, uint8_t *last, int size, int bpp)
static void	png_handle_row (PNGDecContext *s)
static int	png_decode_idat (PNGDecContext *s, int length)
static int	decode_zbuf (AVBPrint *bp, const uint8_t *data, const uint8_t *data_end)
static uint8_t *	iso88591_to_utf8 (const uint8_t *in, size_t size_in)
static int	decode_text_chunk (PNGDecContext *s, uint32_t length, int compressed, AVDictionary **dict)
static int	decode_frame (AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
static int	update_thread_context (AVCodecContext *dst, const AVCodecContext *src)
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_mask [NB_PASSES]
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 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 - bpp; 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 187 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)\
    for (; i < size; i++) {\
        dst[i] = op(dst[i-bpp], src[i], last[i]);\
    }\

Definition at line 203 of file pngdec.c.

Referenced by png_filter_row().

#define OP_SUB	(		x,
			s,
			l
	)		x+s

Referenced by png_filter_row().

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

#define YUV2RGB	(		NAME,
			TYPE
	)

Value:

static void deloco_ ## NAME(TYPE *dst, int size, int alpha) \
{ \
    int i; \
    for (i = 0; i < size; i += 3 + alpha) { \
        int g = dst [i+1]; \
        dst[i+0] += g; \
        dst[i+2] += g; \
    } \
}

Definition at line 267 of file pngdec.c.

Function Documentation

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 90 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 160 of file pngdec.c.

Referenced by ff_pngdsp_init(), and png_filter_row().

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

static

Definition at line 213 of file pngdec.c.

Referenced by png_handle_row().

static void png_handle_row ( PNGDecContext *  s )

static

Definition at line 282 of file pngdec.c.

Referenced by png_decode_idat().

static int png_decode_idat ( PNGDecContext *  s, int  length  )

static

Definition at line 363 of file pngdec.c.

Referenced by decode_frame().

static int decode_zbuf ( AVBPrint *  bp, const uint8_t *  data, const uint8_t *  data_end  )

static

Definition at line 392 of file pngdec.c.

Referenced by decode_text_chunk().

static uint8_t* iso88591_to_utf8 ( const uint8_t *  in, size_t  size_in  )

static

Definition at line 436 of file pngdec.c.

Referenced by decode_text_chunk().

static int decode_text_chunk ( PNGDecContext *  s, uint32_t  length, int  compressed, AVDictionary **  dict  )

static

Definition at line 460 of file pngdec.c.

Referenced by decode_frame().

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

static

Definition at line 508 of file pngdec.c.

static int update_thread_context ( AVCodecContext *  dst, const AVCodecContext *  src  )

static

Definition at line 877 of file pngdec.c.

static av_cold int png_dec_init ( AVCodecContext *  avctx )

static

Definition at line 892 of file pngdec.c.

static av_cold int png_dec_end ( AVCodecContext *  avctx )

static

Definition at line 910 of file pngdec.c.

Variable Documentation

const uint8_t png_pass_mask[NB_PASSES]

static

Initial value:

= {
    0x01, 0x01, 0x11, 0x11, 0x55, 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, 0xff, 0x33, 0xff, 0x55,
}

Definition at line 78 of file pngdec.c.

Referenced by png_handle_row().

const uint8_t png_pass_dsp_mask[NB_PASSES]

static

Initial value:

= {
    0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff
}

Definition at line 83 of file pngdec.c.

Referenced by png_put_interlaced_row().

AVCodec ff_png_decoder

Initial value:

= {
    .name           = "png",
    .long_name      = NULL_IF_CONFIG_SMALL("PNG (Portable Network Graphics) image"),
    .type           = AVMEDIA_TYPE_VIDEO,
    .id             = AV_CODEC_ID_PNG,
    .priv_data_size = sizeof(PNGDecContext),
    .init           = png_dec_init,
    .close          = png_dec_end,
    .decode         = decode_frame,
    .init_thread_copy = ONLY_IF_THREADS_ENABLED(png_dec_init),
    .update_thread_context = ONLY_IF_THREADS_ENABLED(update_thread_context),
    .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS ,
}

Definition at line 928 of file pngdec.c.