pngdec.c File Reference

#include "config_components.h"
#include "libavutil/attributes.h"
#include "libavutil/avassert.h"
#include "libavutil/bprint.h"
#include "libavutil/crc.h"
#include "libavutil/csp.h"
#include "libavutil/imgutils.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/mastering_display_metadata.h"
#include "libavutil/mem.h"
#include "libavutil/pixfmt.h"
#include "libavutil/rational.h"
#include "libavutil/stereo3d.h"
#include "avcodec.h"
#include "bytestream.h"
#include "codec_internal.h"
#include "decode.h"
#include "exif_internal.h"
#include "apng.h"
#include "png.h"
#include "pngdsp.h"
#include "progressframe.h"
#include "thread.h"
#include "zlib_wrapper.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)
#define	OP_AVG(x, s, l)
#define	YUV2RGB(NAME, TYPE)
#define	PNG_ZBUF_MAX_DECOMPRESSED   (16 * 1024 * 1024)
#define	FAST_DIV255(x)

Enumerations
enum	PNGHeaderState { PNG_IHDR = 1 << 0 , PNG_PLTE = 1 << 1 }
enum	PNGImageState { PNG_IDAT = 1 << 0 , PNG_ALLIMAGE = 1 << 1 }

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_png_filter_row (PNGDSPContext *dsp, uint8_t *dst, int filter_type, const uint8_t *src, const uint8_t *last, int size, int bpp)
static int	percent_missing (PNGDecContext *s)
static void	png_handle_row (PNGDecContext *s, uint8_t *dst, ptrdiff_t dst_stride)
static int	png_decode_idat (PNGDecContext *s, GetByteContext *gb, uint8_t *dst, ptrdiff_t dst_stride)
static int	decode_zbuf (AVBPrint *bp, const uint8_t *data, const uint8_t *data_end, void *logctx)
static char *	iso88591_to_utf8 (const char *in, size_t size_in)
static int	decode_text_to_exif (PNGDecContext *s, const char *txt_utf8)
static int	decode_text_chunk (PNGDecContext *s, GetByteContext *gb, int compressed)
static int	decode_ihdr_chunk (AVCodecContext *avctx, PNGDecContext *s, GetByteContext *gb)
static int	decode_phys_chunk (AVCodecContext *avctx, PNGDecContext *s, GetByteContext *gb)
static int	decode_exif_chunk (AVCodecContext *avctx, PNGDecContext *s, GetByteContext *gb)
static int	populate_avctx_color_fields (AVCodecContext *avctx, AVFrame *frame)
static int	decode_idat_chunk (AVCodecContext *avctx, PNGDecContext *s, GetByteContext *gb, AVFrame *p)
static int	decode_plte_chunk (AVCodecContext *avctx, PNGDecContext *s, GetByteContext *gb)
static int	decode_trns_chunk (AVCodecContext *avctx, PNGDecContext *s, GetByteContext *gb)
static int	decode_iccp_chunk (PNGDecContext *s, GetByteContext *gb)
static int	decode_sbit_chunk (AVCodecContext *avctx, PNGDecContext *s, GetByteContext *gb)
static void	handle_small_bpp (PNGDecContext *s, AVFrame *p)
static int	decode_fctl_chunk (AVCodecContext *avctx, PNGDecContext *s, GetByteContext *gb)
static void	handle_p_frame_png (PNGDecContext *s, AVFrame *p)
static int	handle_p_frame_apng (AVCodecContext *avctx, PNGDecContext *s, AVFrame *p)
static void	apng_reset_background (PNGDecContext *s, const AVFrame *p)
static int	decode_frame_common (AVCodecContext *avctx, PNGDecContext *s, AVFrame *p, const AVPacket *avpkt)
static void	clear_frame_metadata (PNGDecContext *s)
static int	output_frame (PNGDecContext *s, AVFrame *f)
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]

Macro Definition Documentation

UNROLL1

#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 222 of file pngdec.c.

UNROLL_FILTER

#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 245 of file pngdec.c.

Referenced by ff_png_filter_row().

OP_SUB

#define OP_SUB	(		x,
			s,
			l )

Value:

((x) + (s))

Referenced by ff_png_filter_row().

OP_AVG

#define OP_AVG	(		x,
			s,
			l )

Value:

(((((x) + (l)) >> 1) + (s)) & 0xff)

YUV2RGB

#define YUV2RGB	(		NAME,
			TYPE )

Value:

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

Definition at line 317 of file pngdec.c.

Referenced by ENDYUV2RGBLINE(), ENDYUV2RGBLINE32(), PUTBGR24(), PUTRGB(), PUTRGB24(), RGB32_PACK(), RGB32_PACK(), RGB32_PACK(), RGB32_STORE(), RGB_PACK(), YUV2RGB(), and YUV2RGB().

PNG_ZBUF_MAX_DECOMPRESSED

#define PNG_ZBUF_MAX_DECOMPRESSED   (16 * 1024 * 1024)

Definition at line 454 of file pngdec.c.

Referenced by decode_zbuf().

FAST_DIV255

#define FAST_DIV255

(

x

)

Value:

((((x) + 128) * 257) >> 16)

Definition at line 1386 of file pngdec.c.

Referenced by handle_p_frame_apng().

Enumeration Type Documentation

PNGHeaderState

enum PNGHeaderState

Enumerator
PNG_IHDR
PNG_PLTE

Definition at line 53 of file pngdec.c.

PNGImageState

enum PNGImageState

Enumerator
PNG_IDAT
PNG_ALLIMAGE

Definition at line 58 of file pngdec.c.

Function Documentation

png_put_interlaced_row()

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 152 of file pngdec.c.

Referenced by png_handle_row().

ff_png_filter_row()

void ff_png_filter_row	(	PNGDSPContext *	dsp,
		uint8_t *	dst,
		int	filter_type,
		const uint8_t *	src,
		const uint8_t *	last,
		int	size,
		int	bpp )

Definition at line 260 of file pngdec.c.

Referenced by handle_row(), and png_handle_row().

percent_missing()

static int percent_missing ( PNGDecContext * s )

static

Definition at line 331 of file pngdec.c.

Referenced by decode_frame_common(), and percent_missing().

png_handle_row()

static void png_handle_row ( PNGDecContext * s, uint8_t * dst, ptrdiff_t dst_stride )

static

Definition at line 341 of file pngdec.c.

Referenced by png_decode_idat().

png_decode_idat()

static int png_decode_idat ( PNGDecContext * s, GetByteContext * gb, uint8_t * dst, ptrdiff_t dst_stride )

static

Definition at line 422 of file pngdec.c.

Referenced by decode_idat_chunk().

decode_zbuf()

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

static

Definition at line 456 of file pngdec.c.

Referenced by decode_iccp_chunk(), and decode_text_chunk().

iso88591_to_utf8()

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

static

Definition at line 505 of file pngdec.c.

Referenced by decode_text_chunk().

decode_text_to_exif()

static int decode_text_to_exif ( PNGDecContext * s, const char * txt_utf8 )

static

Definition at line 529 of file pngdec.c.

Referenced by decode_text_chunk().

decode_text_chunk()

static int decode_text_chunk ( PNGDecContext * s, GetByteContext * gb, int compressed )

static

Definition at line 621 of file pngdec.c.

Referenced by decode_frame_common().

decode_ihdr_chunk()

static int decode_ihdr_chunk ( AVCodecContext * avctx, PNGDecContext * s, GetByteContext * gb )

static

Definition at line 679 of file pngdec.c.

Referenced by decode_frame_common().

decode_phys_chunk()

static int decode_phys_chunk ( AVCodecContext * avctx, PNGDecContext * s, GetByteContext * gb )

static

Definition at line 730 of file pngdec.c.

Referenced by decode_frame_common().

decode_exif_chunk()

static int decode_exif_chunk ( AVCodecContext * avctx, PNGDecContext * s, GetByteContext * gb )

static

Definition at line 746 of file pngdec.c.

Referenced by decode_frame_common().

populate_avctx_color_fields()

static int populate_avctx_color_fields ( AVCodecContext * avctx, AVFrame * frame )

static

Definition at line 768 of file pngdec.c.

Referenced by decode_idat_chunk().

decode_idat_chunk()

static int decode_idat_chunk ( AVCodecContext * avctx, PNGDecContext * s, GetByteContext * gb, AVFrame * p )

static

Definition at line 897 of file pngdec.c.

Referenced by decode_frame_common().

decode_plte_chunk()

static int decode_plte_chunk ( AVCodecContext * avctx, PNGDecContext * s, GetByteContext * gb )

static

Definition at line 1078 of file pngdec.c.

Referenced by decode_frame_common().

decode_trns_chunk()

static int decode_trns_chunk ( AVCodecContext * avctx, PNGDecContext * s, GetByteContext * gb )

static

Definition at line 1101 of file pngdec.c.

Referenced by decode_frame_common().

decode_iccp_chunk()

static int decode_iccp_chunk ( PNGDecContext * s, GetByteContext * gb )

static

Definition at line 1149 of file pngdec.c.

Referenced by decode_frame_common().

decode_sbit_chunk()

static int decode_sbit_chunk ( AVCodecContext * avctx, PNGDecContext * s, GetByteContext * gb )

static

Definition at line 1182 of file pngdec.c.

Referenced by decode_frame_common().

handle_small_bpp()

static void handle_small_bpp ( PNGDecContext * s, AVFrame * p )

static

Definition at line 1222 of file pngdec.c.

Referenced by decode_frame_common().

decode_fctl_chunk()

static int decode_fctl_chunk ( AVCodecContext * avctx, PNGDecContext * s, GetByteContext * gb )

static

Definition at line 1295 of file pngdec.c.

Referenced by decode_frame_common().

handle_p_frame_png()

static void handle_p_frame_png ( PNGDecContext * s, AVFrame * p )

static

Definition at line 1366 of file pngdec.c.

Referenced by decode_frame_common().

handle_p_frame_apng()

static int handle_p_frame_apng ( AVCodecContext * avctx, PNGDecContext * s, AVFrame * p )

static

Definition at line 1388 of file pngdec.c.

Referenced by decode_frame_common().

apng_reset_background()

static void apng_reset_background ( PNGDecContext * s, const AVFrame * p )

static

Definition at line 1477 of file pngdec.c.

Referenced by decode_frame_common().

decode_frame_common()

static int decode_frame_common ( AVCodecContext * avctx, PNGDecContext * s, AVFrame * p, const AVPacket * avpkt )

static

Definition at line 1493 of file pngdec.c.

clear_frame_metadata()

static void clear_frame_metadata ( PNGDecContext * s )

static

Definition at line 1838 of file pngdec.c.

output_frame()

static int output_frame ( PNGDecContext * s, AVFrame * f )

static

Definition at line 1853 of file pngdec.c.

png_dec_init()

static av_cold int png_dec_init ( AVCodecContext * avctx )

static

Definition at line 2019 of file pngdec.c.

png_dec_end()

static av_cold int png_dec_end ( AVCodecContext * avctx )

static

Definition at line 2030 of file pngdec.c.

Variable Documentation

png_pass_mask

const uint8_t png_pass_mask[NB_PASSES]

static

Initial value:

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

Definition at line 135 of file pngdec.c.

Referenced by png_put_interlaced_row().

png_pass_dsp_ymask

const uint8_t png_pass_dsp_ymask[NB_PASSES]

static

Initial value:

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

Definition at line 140 of file pngdec.c.

Referenced by png_handle_row().

png_pass_dsp_mask

const uint8_t png_pass_dsp_mask[NB_PASSES]

static

Initial value:

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

Definition at line 145 of file pngdec.c.

Referenced by png_put_interlaced_row().