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swscale_internal.h
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/*
* Copyright (C) 2001-2011 Michael Niedermayer <[email protected]>
*
* 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
*/
#ifndef SWSCALE_SWSCALE_INTERNAL_H
#define SWSCALE_SWSCALE_INTERNAL_H
#include "config.h"
#include "version.h"
#include "libavutil/avassert.h"
#include "libavutil/avutil.h"
#include "libavutil/common.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/log.h"
#include "libavutil/pixfmt.h"
#include "libavutil/pixdesc.h"
#include "libavutil/ppc/util_altivec.h"
#define STR(s) AV_TOSTRING(s) // AV_STRINGIFY is too long
#define YUVRGB_TABLE_HEADROOM 512
#define YUVRGB_TABLE_LUMA_HEADROOM 512
#define MAX_FILTER_SIZE SWS_MAX_FILTER_SIZE
#define DITHER1XBPP
#if HAVE_BIGENDIAN
#define ALT32_CORR (-1)
#else
#define ALT32_CORR 1
#endif
#if ARCH_X86_64
# define APCK_PTR2 8
# define APCK_COEF 16
# define APCK_SIZE 24
#else
# define APCK_PTR2 4
# define APCK_COEF 8
# define APCK_SIZE 16
#endif
#define RETCODE_USE_CASCADE -12345
struct SwsContext;
typedef enum SwsDither {
SWS_DITHER_NONE = 0,
SWS_DITHER_AUTO,
SWS_DITHER_BAYER,
SWS_DITHER_ED,
SWS_DITHER_A_DITHER,
SWS_DITHER_X_DITHER,
NB_SWS_DITHER,
} SwsDither;
typedef enum SwsAlphaBlend {
SWS_ALPHA_BLEND_NONE = 0,
SWS_ALPHA_BLEND_UNIFORM,
SWS_ALPHA_BLEND_CHECKERBOARD,
SWS_ALPHA_BLEND_NB,
} SwsAlphaBlend;
typedef int (*SwsFunc)(struct SwsContext *context, const uint8_t *src[],
int srcStride[], int srcSliceY, int srcSliceH,
uint8_t *dst[], int dstStride[]);
/**
* Write one line of horizontally scaled data to planar output
* without any additional vertical scaling (or point-scaling).
*
* @param src scaled source data, 15 bits for 8-10-bit output,
* 19 bits for 16-bit output (in int32_t)
* @param dest pointer to the output plane. For >8-bit
* output, this is in uint16_t
* @param dstW width of destination in pixels
* @param dither ordered dither array of type int16_t and size 8
* @param offset Dither offset
*/
typedef void (*yuv2planar1_fn)(const int16_t *src, uint8_t *dest, int dstW,
const uint8_t *dither, int offset);
/**
* Write one line of horizontally scaled data to planar output
* with multi-point vertical scaling between input pixels.
*
* @param filter vertical luma/alpha scaling coefficients, 12 bits [0,4096]
* @param src scaled luma (Y) or alpha (A) source data, 15 bits for
* 8-10-bit output, 19 bits for 16-bit output (in int32_t)
* @param filterSize number of vertical input lines to scale
* @param dest pointer to output plane. For >8-bit
* output, this is in uint16_t
* @param dstW width of destination pixels
* @param offset Dither offset
*/
typedef void (*yuv2planarX_fn)(const int16_t *filter, int filterSize,
const int16_t **src, uint8_t *dest, int dstW,
const uint8_t *dither, int offset);
/**
* Write one line of horizontally scaled chroma to interleaved output
* with multi-point vertical scaling between input pixels.
*
* @param c SWS scaling context
* @param chrFilter vertical chroma scaling coefficients, 12 bits [0,4096]
* @param chrUSrc scaled chroma (U) source data, 15 bits for 8-10-bit
* output, 19 bits for 16-bit output (in int32_t)
* @param chrVSrc scaled chroma (V) source data, 15 bits for 8-10-bit
* output, 19 bits for 16-bit output (in int32_t)
* @param chrFilterSize number of vertical chroma input lines to scale
* @param dest pointer to the output plane. For >8-bit
* output, this is in uint16_t
* @param dstW width of chroma planes
*/
typedef void (*yuv2interleavedX_fn)(struct SwsContext *c,
const int16_t *chrFilter,
int chrFilterSize,
const int16_t **chrUSrc,
const int16_t **chrVSrc,
uint8_t *dest, int dstW);
/**
* Write one line of horizontally scaled Y/U/V/A to packed-pixel YUV/RGB
* output without any additional vertical scaling (or point-scaling). Note
* that this function may do chroma scaling, see the "uvalpha" argument.
*
* @param c SWS scaling context
* @param lumSrc scaled luma (Y) source data, 15 bits for 8-10-bit output,
* 19 bits for 16-bit output (in int32_t)
* @param chrUSrc scaled chroma (U) source data, 15 bits for 8-10-bit output,
* 19 bits for 16-bit output (in int32_t)
* @param chrVSrc scaled chroma (V) source data, 15 bits for 8-10-bit output,
* 19 bits for 16-bit output (in int32_t)
* @param alpSrc scaled alpha (A) source data, 15 bits for 8-10-bit output,
* 19 bits for 16-bit output (in int32_t)
* @param dest pointer to the output plane. For 16-bit output, this is
* uint16_t
* @param dstW width of lumSrc and alpSrc in pixels, number of pixels
* to write into dest[]
* @param uvalpha chroma scaling coefficient for the second line of chroma
* pixels, either 2048 or 0. If 0, one chroma input is used
* for 2 output pixels (or if the SWS_FLAG_FULL_CHR_INT flag
* is set, it generates 1 output pixel). If 2048, two chroma
* input pixels should be averaged for 2 output pixels (this
* only happens if SWS_FLAG_FULL_CHR_INT is not set)
* @param y vertical line number for this output. This does not need
* to be used to calculate the offset in the destination,
* but can be used to generate comfort noise using dithering
* for some output formats.
*/
typedef void (*yuv2packed1_fn)(struct SwsContext *c, const int16_t *lumSrc,
const int16_t *chrUSrc[2],
const int16_t *chrVSrc[2],
const int16_t *alpSrc, uint8_t *dest,
int dstW, int uvalpha, int y);
/**
* Write one line of horizontally scaled Y/U/V/A to packed-pixel YUV/RGB
* output by doing bilinear scaling between two input lines.
*
* @param c SWS scaling context
* @param lumSrc scaled luma (Y) source data, 15 bits for 8-10-bit output,
* 19 bits for 16-bit output (in int32_t)
* @param chrUSrc scaled chroma (U) source data, 15 bits for 8-10-bit output,
* 19 bits for 16-bit output (in int32_t)
* @param chrVSrc scaled chroma (V) source data, 15 bits for 8-10-bit output,
* 19 bits for 16-bit output (in int32_t)
* @param alpSrc scaled alpha (A) source data, 15 bits for 8-10-bit output,
* 19 bits for 16-bit output (in int32_t)
* @param dest pointer to the output plane. For 16-bit output, this is
* uint16_t
* @param dstW width of lumSrc and alpSrc in pixels, number of pixels
* to write into dest[]
* @param yalpha luma/alpha scaling coefficients for the second input line.
* The first line's coefficients can be calculated by using
* 4096 - yalpha
* @param uvalpha chroma scaling coefficient for the second input line. The
* first line's coefficients can be calculated by using
* 4096 - uvalpha
* @param y vertical line number for this output. This does not need
* to be used to calculate the offset in the destination,
* but can be used to generate comfort noise using dithering
* for some output formats.
*/
typedef void (*yuv2packed2_fn)(struct SwsContext *c, const int16_t *lumSrc[2],
const int16_t *chrUSrc[2],
const int16_t *chrVSrc[2],
const int16_t *alpSrc[2],
uint8_t *dest,
int dstW, int yalpha, int uvalpha, int y);
/**
* Write one line of horizontally scaled Y/U/V/A to packed-pixel YUV/RGB
* output by doing multi-point vertical scaling between input pixels.
*
* @param c SWS scaling context
* @param lumFilter vertical luma/alpha scaling coefficients, 12 bits [0,4096]
* @param lumSrc scaled luma (Y) source data, 15 bits for 8-10-bit output,
* 19 bits for 16-bit output (in int32_t)
* @param lumFilterSize number of vertical luma/alpha input lines to scale
* @param chrFilter vertical chroma scaling coefficients, 12 bits [0,4096]
* @param chrUSrc scaled chroma (U) source data, 15 bits for 8-10-bit output,
* 19 bits for 16-bit output (in int32_t)
* @param chrVSrc scaled chroma (V) source data, 15 bits for 8-10-bit output,
* 19 bits for 16-bit output (in int32_t)
* @param chrFilterSize number of vertical chroma input lines to scale
* @param alpSrc scaled alpha (A) source data, 15 bits for 8-10-bit output,
* 19 bits for 16-bit output (in int32_t)
* @param dest pointer to the output plane. For 16-bit output, this is
* uint16_t
* @param dstW width of lumSrc and alpSrc in pixels, number of pixels
* to write into dest[]
* @param y vertical line number for this output. This does not need
* to be used to calculate the offset in the destination,
* but can be used to generate comfort noise using dithering
* or some output formats.
*/
typedef void (*yuv2packedX_fn)(struct SwsContext *c, const int16_t *lumFilter,
const int16_t **lumSrc, int lumFilterSize,
const int16_t *chrFilter,
const int16_t **chrUSrc,
const int16_t **chrVSrc, int chrFilterSize,
const int16_t **alpSrc, uint8_t *dest,
int dstW, int y);
/**
* Write one line of horizontally scaled Y/U/V/A to YUV/RGB
* output by doing multi-point vertical scaling between input pixels.
*
* @param c SWS scaling context
* @param lumFilter vertical luma/alpha scaling coefficients, 12 bits [0,4096]
* @param lumSrc scaled luma (Y) source data, 15 bits for 8-10-bit output,
* 19 bits for 16-bit output (in int32_t)
* @param lumFilterSize number of vertical luma/alpha input lines to scale
* @param chrFilter vertical chroma scaling coefficients, 12 bits [0,4096]
* @param chrUSrc scaled chroma (U) source data, 15 bits for 8-10-bit output,
* 19 bits for 16-bit output (in int32_t)
* @param chrVSrc scaled chroma (V) source data, 15 bits for 8-10-bit output,
* 19 bits for 16-bit output (in int32_t)
* @param chrFilterSize number of vertical chroma input lines to scale
* @param alpSrc scaled alpha (A) source data, 15 bits for 8-10-bit output,
* 19 bits for 16-bit output (in int32_t)
* @param dest pointer to the output planes. For 16-bit output, this is
* uint16_t
* @param dstW width of lumSrc and alpSrc in pixels, number of pixels
* to write into dest[]
* @param y vertical line number for this output. This does not need
* to be used to calculate the offset in the destination,
* but can be used to generate comfort noise using dithering
* or some output formats.
*/
typedef void (*yuv2anyX_fn)(struct SwsContext *c, const int16_t *lumFilter,
const int16_t **lumSrc, int lumFilterSize,
const int16_t *chrFilter,
const int16_t **chrUSrc,
const int16_t **chrVSrc, int chrFilterSize,
const int16_t **alpSrc, uint8_t **dest,
int dstW, int y);
struct SwsSlice;
struct SwsFilterDescriptor;
/* This struct should be aligned on at least a 32-byte boundary. */
typedef struct SwsContext {
/**
* info on struct for av_log
*/
const AVClass *av_class;
/**
* Note that src, dst, srcStride, dstStride will be copied in the
* sws_scale() wrapper so they can be freely modified here.
*/
SwsFunc swscale;
int srcW; ///< Width of source luma/alpha planes.
int srcH; ///< Height of source luma/alpha planes.
int dstH; ///< Height of destination luma/alpha planes.
int chrSrcW; ///< Width of source chroma planes.
int chrSrcH; ///< Height of source chroma planes.
int chrDstW; ///< Width of destination chroma planes.
int chrDstH; ///< Height of destination chroma planes.
int lumXInc, chrXInc;
int lumYInc, chrYInc;
enum AVPixelFormat dstFormat; ///< Destination pixel format.
enum AVPixelFormat srcFormat; ///< Source pixel format.
int dstFormatBpp; ///< Number of bits per pixel of the destination pixel format.
int srcFormatBpp; ///< Number of bits per pixel of the source pixel format.
int dstBpc, srcBpc;
int chrSrcHSubSample; ///< Binary logarithm of horizontal subsampling factor between luma/alpha and chroma planes in source image.
int chrSrcVSubSample; ///< Binary logarithm of vertical subsampling factor between luma/alpha and chroma planes in source image.
int chrDstHSubSample; ///< Binary logarithm of horizontal subsampling factor between luma/alpha and chroma planes in destination image.
int chrDstVSubSample; ///< Binary logarithm of vertical subsampling factor between luma/alpha and chroma planes in destination image.
int vChrDrop; ///< Binary logarithm of extra vertical subsampling factor in source image chroma planes specified by user.
int sliceDir; ///< Direction that slices are fed to the scaler (1 = top-to-bottom, -1 = bottom-to-top).
double param[2]; ///< Input parameters for scaling algorithms that need them.
/* The cascaded_* fields allow spliting a scaler task into multiple
* sequential steps, this is for example used to limit the maximum
* downscaling factor that needs to be supported in one scaler.
*/
struct SwsContext *cascaded_context[3];
int cascaded_tmpStride[4];
uint8_t *cascaded_tmp[4];
int cascaded1_tmpStride[4];
uint8_t *cascaded1_tmp[4];
int cascaded_mainindex;
double gamma_value;
int gamma_flag;
int is_internal_gamma;
uint16_t *gamma;
uint16_t *inv_gamma;
int numDesc;
int descIndex[2];
int numSlice;
struct SwsSlice *slice;
struct SwsFilterDescriptor *desc;
uint32_t pal_yuv[256];
uint32_t pal_rgb[256];
float uint2float_lut[256];
/**
* @name Scaled horizontal lines ring buffer.
* The horizontal scaler keeps just enough scaled lines in a ring buffer
* so they may be passed to the vertical scaler. The pointers to the
* allocated buffers for each line are duplicated in sequence in the ring
* buffer to simplify indexing and avoid wrapping around between lines
* inside the vertical scaler code. The wrapping is done before the
* vertical scaler is called.
*/
//@{
int lastInLumBuf; ///< Last scaled horizontal luma/alpha line from source in the ring buffer.
int lastInChrBuf; ///< Last scaled horizontal chroma line from source in the ring buffer.
//@}
uint8_t *formatConvBuffer;
int needAlpha;
/**
* @name Horizontal and vertical filters.
* To better understand the following fields, here is a pseudo-code of
* their usage in filtering a horizontal line:
* @code
* for (i = 0; i < width; i++) {
* dst[i] = 0;
* for (j = 0; j < filterSize; j++)
* dst[i] += src[ filterPos[i] + j ] * filter[ filterSize * i + j ];
* dst[i] >>= FRAC_BITS; // The actual implementation is fixed-point.
* }
* @endcode
*/
//@{
int16_t *hLumFilter; ///< Array of horizontal filter coefficients for luma/alpha planes.
int16_t *hChrFilter; ///< Array of horizontal filter coefficients for chroma planes.
int16_t *vLumFilter; ///< Array of vertical filter coefficients for luma/alpha planes.
int16_t *vChrFilter; ///< Array of vertical filter coefficients for chroma planes.
int32_t *hLumFilterPos; ///< Array of horizontal filter starting positions for each dst[i] for luma/alpha planes.
int32_t *hChrFilterPos; ///< Array of horizontal filter starting positions for each dst[i] for chroma planes.
int32_t *vLumFilterPos; ///< Array of vertical filter starting positions for each dst[i] for luma/alpha planes.
int32_t *vChrFilterPos; ///< Array of vertical filter starting positions for each dst[i] for chroma planes.
int hLumFilterSize; ///< Horizontal filter size for luma/alpha pixels.
int hChrFilterSize; ///< Horizontal filter size for chroma pixels.
int vLumFilterSize; ///< Vertical filter size for luma/alpha pixels.
int vChrFilterSize; ///< Vertical filter size for chroma pixels.
//@}
int lumMmxextFilterCodeSize; ///< Runtime-generated MMXEXT horizontal fast bilinear scaler code size for luma/alpha planes.
int chrMmxextFilterCodeSize; ///< Runtime-generated MMXEXT horizontal fast bilinear scaler code size for chroma planes.
uint8_t *lumMmxextFilterCode; ///< Runtime-generated MMXEXT horizontal fast bilinear scaler code for luma/alpha planes.
uint8_t *chrMmxextFilterCode; ///< Runtime-generated MMXEXT horizontal fast bilinear scaler code for chroma planes.
int canMMXEXTBeUsed;
int warned_unuseable_bilinear;
int dstY; ///< Last destination vertical line output from last slice.
int flags; ///< Flags passed by the user to select scaler algorithm, optimizations, subsampling, etc...
void *yuvTable; // pointer to the yuv->rgb table start so it can be freed()
// alignment ensures the offset can be added in a single
// instruction on e.g. ARM
DECLARE_ALIGNED(16, int, table_gV)[256 + 2*YUVRGB_TABLE_HEADROOM];
uint8_t *table_rV[256 + 2*YUVRGB_TABLE_HEADROOM];
uint8_t *table_gU[256 + 2*YUVRGB_TABLE_HEADROOM];
uint8_t *table_bU[256 + 2*YUVRGB_TABLE_HEADROOM];
DECLARE_ALIGNED(16, int32_t, input_rgb2yuv_table)[16+40*4]; // This table can contain both C and SIMD formatted values, the C vales are always at the XY_IDX points
#define RY_IDX 0
#define GY_IDX 1
#define BY_IDX 2
#define RU_IDX 3
#define GU_IDX 4
#define BU_IDX 5
#define RV_IDX 6
#define GV_IDX 7
#define BV_IDX 8
#define RGB2YUV_SHIFT 15
int *dither_error[4];
//Colorspace stuff
int contrast, brightness, saturation; // for sws_getColorspaceDetails
int srcColorspaceTable[4];
int dstColorspaceTable[4];
int srcRange; ///< 0 = MPG YUV range, 1 = JPG YUV range (source image).
int dstRange; ///< 0 = MPG YUV range, 1 = JPG YUV range (destination image).
int src0Alpha;
int dst0Alpha;
int srcXYZ;
int dstXYZ;
int src_h_chr_pos;
int dst_h_chr_pos;
int src_v_chr_pos;
int dst_v_chr_pos;
int yuv2rgb_y_offset;
int yuv2rgb_y_coeff;
int yuv2rgb_v2r_coeff;
int yuv2rgb_v2g_coeff;
int yuv2rgb_u2g_coeff;
int yuv2rgb_u2b_coeff;
#define RED_DITHER "0*8"
#define GREEN_DITHER "1*8"
#define BLUE_DITHER "2*8"
#define Y_COEFF "3*8"
#define VR_COEFF "4*8"
#define UB_COEFF "5*8"
#define VG_COEFF "6*8"
#define UG_COEFF "7*8"
#define Y_OFFSET "8*8"
#define U_OFFSET "9*8"
#define V_OFFSET "10*8"
#define LUM_MMX_FILTER_OFFSET "11*8"
#define CHR_MMX_FILTER_OFFSET "11*8+4*4*"AV_STRINGIFY(MAX_FILTER_SIZE)
#define DSTW_OFFSET "11*8+4*4*"AV_STRINGIFY(MAX_FILTER_SIZE)"*2"
#define ESP_OFFSET "11*8+4*4*"AV_STRINGIFY(MAX_FILTER_SIZE)"*2+8"
#define VROUNDER_OFFSET "11*8+4*4*"AV_STRINGIFY(MAX_FILTER_SIZE)"*2+16"
#define U_TEMP "11*8+4*4*"AV_STRINGIFY(MAX_FILTER_SIZE)"*2+24"
#define V_TEMP "11*8+4*4*"AV_STRINGIFY(MAX_FILTER_SIZE)"*2+32"
#define Y_TEMP "11*8+4*4*"AV_STRINGIFY(MAX_FILTER_SIZE)"*2+40"
#define ALP_MMX_FILTER_OFFSET "11*8+4*4*"AV_STRINGIFY(MAX_FILTER_SIZE)"*2+48"
#define UV_OFF_PX "11*8+4*4*"AV_STRINGIFY(MAX_FILTER_SIZE)"*3+48"
#define UV_OFF_BYTE "11*8+4*4*"AV_STRINGIFY(MAX_FILTER_SIZE)"*3+56"
#define DITHER16 "11*8+4*4*"AV_STRINGIFY(MAX_FILTER_SIZE)"*3+64"
#define DITHER32 "11*8+4*4*"AV_STRINGIFY(MAX_FILTER_SIZE)"*3+80"
#define DITHER32_INT (11*8+4*4*MAX_FILTER_SIZE*3+80) // value equal to above, used for checking that the struct hasn't been changed by mistake
DECLARE_ALIGNED(8, uint64_t, redDither);
DECLARE_ALIGNED(8, uint64_t, greenDither);
DECLARE_ALIGNED(8, uint64_t, blueDither);
DECLARE_ALIGNED(8, uint64_t, yCoeff);
DECLARE_ALIGNED(8, uint64_t, vrCoeff);
DECLARE_ALIGNED(8, uint64_t, ubCoeff);
DECLARE_ALIGNED(8, uint64_t, vgCoeff);
DECLARE_ALIGNED(8, uint64_t, ugCoeff);
DECLARE_ALIGNED(8, uint64_t, yOffset);
DECLARE_ALIGNED(8, uint64_t, uOffset);
DECLARE_ALIGNED(8, uint64_t, vOffset);
int32_t lumMmxFilter[4 * MAX_FILTER_SIZE];
int32_t chrMmxFilter[4 * MAX_FILTER_SIZE];
int dstW; ///< Width of destination luma/alpha planes.
DECLARE_ALIGNED(8, uint64_t, esp);
DECLARE_ALIGNED(8, uint64_t, vRounder);
DECLARE_ALIGNED(8, uint64_t, u_temp);
DECLARE_ALIGNED(8, uint64_t, v_temp);
DECLARE_ALIGNED(8, uint64_t, y_temp);
int32_t alpMmxFilter[4 * MAX_FILTER_SIZE];
// alignment of these values is not necessary, but merely here
// to maintain the same offset across x8632 and x86-64. Once we
// use proper offset macros in the asm, they can be removed.
DECLARE_ALIGNED(8, ptrdiff_t, uv_off); ///< offset (in pixels) between u and v planes
DECLARE_ALIGNED(8, ptrdiff_t, uv_offx2); ///< offset (in bytes) between u and v planes
DECLARE_ALIGNED(8, uint16_t, dither16)[8];
DECLARE_ALIGNED(8, uint32_t, dither32)[8];
const uint8_t *chrDither8, *lumDither8;
#if HAVE_ALTIVEC
vector signed short CY;
vector signed short CRV;
vector signed short CBU;
vector signed short CGU;
vector signed short CGV;
vector signed short OY;
vector unsigned short CSHIFT;
vector signed short *vYCoeffsBank, *vCCoeffsBank;
#endif
int use_mmx_vfilter;
/* pre defined color-spaces gamma */
#define XYZ_GAMMA (2.6f)
#define RGB_GAMMA (2.2f)
int16_t *xyzgamma;
int16_t *rgbgamma;
int16_t *xyzgammainv;
int16_t *rgbgammainv;
int16_t xyz2rgb_matrix[3][4];
int16_t rgb2xyz_matrix[3][4];
/* function pointers for swscale() */
yuv2planar1_fn yuv2plane1;
yuv2planarX_fn yuv2planeX;
yuv2interleavedX_fn yuv2nv12cX;
yuv2packed1_fn yuv2packed1;
yuv2packed2_fn yuv2packed2;
yuv2packedX_fn yuv2packedX;
yuv2anyX_fn yuv2anyX;
/// Unscaled conversion of luma plane to YV12 for horizontal scaler.
void (*lumToYV12)(uint8_t *dst, const uint8_t *src, const uint8_t *src2, const uint8_t *src3,
int width, uint32_t *pal);
/// Unscaled conversion of alpha plane to YV12 for horizontal scaler.
void (*alpToYV12)(uint8_t *dst, const uint8_t *src, const uint8_t *src2, const uint8_t *src3,
int width, uint32_t *pal);
/// Unscaled conversion of chroma planes to YV12 for horizontal scaler.
void (*chrToYV12)(uint8_t *dstU, uint8_t *dstV,
const uint8_t *src1, const uint8_t *src2, const uint8_t *src3,
int width, uint32_t *pal);
/**
* Functions to read planar input, such as planar RGB, and convert
* internally to Y/UV/A.
*/
/** @{ */
void (*readLumPlanar)(uint8_t *dst, const uint8_t *src[4], int width, int32_t *rgb2yuv);
void (*readChrPlanar)(uint8_t *dstU, uint8_t *dstV, const uint8_t *src[4],
int width, int32_t *rgb2yuv);
void (*readAlpPlanar)(uint8_t *dst, const uint8_t *src[4], int width, int32_t *rgb2yuv);
/** @} */
/**
* Scale one horizontal line of input data using a bilinear filter
* to produce one line of output data. Compared to SwsContext->hScale(),
* please take note of the following caveats when using these:
* - Scaling is done using only 7 bits instead of 14-bit coefficients.
* - You can use no more than 5 input pixels to produce 4 output
* pixels. Therefore, this filter should not be used for downscaling
* by more than ~20% in width (because that equals more than 5/4th
* downscaling and thus more than 5 pixels input per 4 pixels output).
* - In general, bilinear filters create artifacts during downscaling
* (even when <20%), because one output pixel will span more than one
* input pixel, and thus some pixels will need edges of both neighbor
* pixels to interpolate the output pixel. Since you can use at most
* two input pixels per output pixel in bilinear scaling, this is
* impossible and thus downscaling by any size will create artifacts.
* To enable this type of scaling, set SWS_FLAG_FAST_BILINEAR
* in SwsContext->flags.
*/
/** @{ */
void (*hyscale_fast)(struct SwsContext *c,
int16_t *dst, int dstWidth,
const uint8_t *src, int srcW, int xInc);
void (*hcscale_fast)(struct SwsContext *c,
int16_t *dst1, int16_t *dst2, int dstWidth,
const uint8_t *src1, const uint8_t *src2,
int srcW, int xInc);
/** @} */
/**
* Scale one horizontal line of input data using a filter over the input
* lines, to produce one (differently sized) line of output data.
*
* @param dst pointer to destination buffer for horizontally scaled
* data. If the number of bits per component of one
* destination pixel (SwsContext->dstBpc) is <= 10, data
* will be 15 bpc in 16 bits (int16_t) width. Else (i.e.
* SwsContext->dstBpc == 16), data will be 19bpc in
* 32 bits (int32_t) width.
* @param dstW width of destination image
* @param src pointer to source data to be scaled. If the number of
* bits per component of a source pixel (SwsContext->srcBpc)
* is 8, this is 8bpc in 8 bits (uint8_t) width. Else
* (i.e. SwsContext->dstBpc > 8), this is native depth
* in 16 bits (uint16_t) width. In other words, for 9-bit
* YUV input, this is 9bpc, for 10-bit YUV input, this is
* 10bpc, and for 16-bit RGB or YUV, this is 16bpc.
* @param filter filter coefficients to be used per output pixel for
* scaling. This contains 14bpp filtering coefficients.
* Guaranteed to contain dstW * filterSize entries.
* @param filterPos position of the first input pixel to be used for
* each output pixel during scaling. Guaranteed to
* contain dstW entries.
* @param filterSize the number of input coefficients to be used (and
* thus the number of input pixels to be used) for
* creating a single output pixel. Is aligned to 4
* (and input coefficients thus padded with zeroes)
* to simplify creating SIMD code.
*/
/** @{ */
void (*hyScale)(struct SwsContext *c, int16_t *dst, int dstW,
const uint8_t *src, const int16_t *filter,
const int32_t *filterPos, int filterSize);
void (*hcScale)(struct SwsContext *c, int16_t *dst, int dstW,
const uint8_t *src, const int16_t *filter,
const int32_t *filterPos, int filterSize);
/** @} */
/// Color range conversion function for luma plane if needed.
void (*lumConvertRange)(int16_t *dst, int width);
/// Color range conversion function for chroma planes if needed.
void (*chrConvertRange)(int16_t *dst1, int16_t *dst2, int width);
int needs_hcscale; ///< Set if there are chroma planes to be converted.
SwsDither dither;
SwsAlphaBlend alphablend;
} SwsContext;
//FIXME check init (where 0)
SwsFunc ff_yuv2rgb_get_func_ptr(SwsContext *c);
int ff_yuv2rgb_c_init_tables(SwsContext *c, const int inv_table[4],
int fullRange, int brightness,
int contrast, int saturation);
void ff_yuv2rgb_init_tables_ppc(SwsContext *c, const int inv_table[4],
int brightness, int contrast, int saturation);
void ff_updateMMXDitherTables(SwsContext *c, int dstY);
av_cold void ff_sws_init_range_convert(SwsContext *c);
SwsFunc ff_yuv2rgb_init_x86(SwsContext *c);
SwsFunc ff_yuv2rgb_init_ppc(SwsContext *c);
static av_always_inline int is16BPS(enum AVPixelFormat pix_fmt)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
av_assert0(desc);
return desc->comp[0].depth == 16;
}
static av_always_inline int is32BPS(enum AVPixelFormat pix_fmt)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
av_assert0(desc);
return desc->comp[0].depth == 32;
}
static av_always_inline int isNBPS(enum AVPixelFormat pix_fmt)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
av_assert0(desc);
return desc->comp[0].depth >= 9 && desc->comp[0].depth <= 14;
}
static av_always_inline int isBE(enum AVPixelFormat pix_fmt)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
av_assert0(desc);
return desc->flags & AV_PIX_FMT_FLAG_BE;
}
static av_always_inline int isYUV(enum AVPixelFormat pix_fmt)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
av_assert0(desc);
return !(desc->flags & AV_PIX_FMT_FLAG_RGB) && desc->nb_components >= 2;
}
static av_always_inline int isPlanarYUV(enum AVPixelFormat pix_fmt)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
av_assert0(desc);
return ((desc->flags & AV_PIX_FMT_FLAG_PLANAR) && isYUV(pix_fmt));
}
/*
* Identity semi-planar YUV formats. Specifically, those are YUV formats
* where the second and third components (U & V) are on the same plane.
*/
static av_always_inline int isSemiPlanarYUV(enum AVPixelFormat pix_fmt)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
av_assert0(desc);
return (isPlanarYUV(pix_fmt) && desc->comp[1].plane == desc->comp[2].plane);
}
static av_always_inline int isRGB(enum AVPixelFormat pix_fmt)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
av_assert0(desc);
return (desc->flags & AV_PIX_FMT_FLAG_RGB);
}
static av_always_inline int isGray(enum AVPixelFormat pix_fmt)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
av_assert0(desc);
return !(desc->flags & AV_PIX_FMT_FLAG_PAL) &&
!(desc->flags & AV_PIX_FMT_FLAG_HWACCEL) &&
desc->nb_components <= 2 &&
pix_fmt != AV_PIX_FMT_MONOBLACK &&
pix_fmt != AV_PIX_FMT_MONOWHITE;
}
static av_always_inline int isRGBinInt(enum AVPixelFormat pix_fmt)
{
return pix_fmt == AV_PIX_FMT_RGB48BE ||
pix_fmt == AV_PIX_FMT_RGB48LE ||
pix_fmt == AV_PIX_FMT_RGB32 ||
pix_fmt == AV_PIX_FMT_RGB32_1 ||
pix_fmt == AV_PIX_FMT_RGB24 ||
pix_fmt == AV_PIX_FMT_RGB565BE ||
pix_fmt == AV_PIX_FMT_RGB565LE ||
pix_fmt == AV_PIX_FMT_RGB555BE ||
pix_fmt == AV_PIX_FMT_RGB555LE ||
pix_fmt == AV_PIX_FMT_RGB444BE ||
pix_fmt == AV_PIX_FMT_RGB444LE ||
pix_fmt == AV_PIX_FMT_RGB8 ||
pix_fmt == AV_PIX_FMT_RGB4 ||
pix_fmt == AV_PIX_FMT_RGB4_BYTE ||
pix_fmt == AV_PIX_FMT_RGBA64BE ||
pix_fmt == AV_PIX_FMT_RGBA64LE ||
pix_fmt == AV_PIX_FMT_MONOBLACK ||
pix_fmt == AV_PIX_FMT_MONOWHITE;
}
static av_always_inline int isBGRinInt(enum AVPixelFormat pix_fmt)
{
return pix_fmt == AV_PIX_FMT_BGR48BE ||
pix_fmt == AV_PIX_FMT_BGR48LE ||
pix_fmt == AV_PIX_FMT_BGR32 ||
pix_fmt == AV_PIX_FMT_BGR32_1 ||
pix_fmt == AV_PIX_FMT_BGR24 ||
pix_fmt == AV_PIX_FMT_BGR565BE ||
pix_fmt == AV_PIX_FMT_BGR565LE ||
pix_fmt == AV_PIX_FMT_BGR555BE ||
pix_fmt == AV_PIX_FMT_BGR555LE ||
pix_fmt == AV_PIX_FMT_BGR444BE ||
pix_fmt == AV_PIX_FMT_BGR444LE ||
pix_fmt == AV_PIX_FMT_BGR8 ||
pix_fmt == AV_PIX_FMT_BGR4 ||
pix_fmt == AV_PIX_FMT_BGR4_BYTE ||
pix_fmt == AV_PIX_FMT_BGRA64BE ||
pix_fmt == AV_PIX_FMT_BGRA64LE ||
pix_fmt == AV_PIX_FMT_MONOBLACK ||
pix_fmt == AV_PIX_FMT_MONOWHITE;
}
static av_always_inline int isBayer(enum AVPixelFormat pix_fmt)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
av_assert0(desc);
return !!(desc->flags & AV_PIX_FMT_FLAG_BAYER);
}
static av_always_inline int isAnyRGB(enum AVPixelFormat pix_fmt)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
av_assert0(desc);
return (desc->flags & AV_PIX_FMT_FLAG_RGB) ||
pix_fmt == AV_PIX_FMT_MONOBLACK || pix_fmt == AV_PIX_FMT_MONOWHITE;
}
static av_always_inline int isFloat(enum AVPixelFormat pix_fmt)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
av_assert0(desc);
return desc->flags & AV_PIX_FMT_FLAG_FLOAT;
}
static av_always_inline int isALPHA(enum AVPixelFormat pix_fmt)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
av_assert0(desc);
if (pix_fmt == AV_PIX_FMT_PAL8)
return 1;
return desc->flags & AV_PIX_FMT_FLAG_ALPHA;
}
static av_always_inline int isPacked(enum AVPixelFormat pix_fmt)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
av_assert0(desc);
return (desc->nb_components >= 2 && !(desc->flags & AV_PIX_FMT_FLAG_PLANAR)) ||
pix_fmt == AV_PIX_FMT_PAL8 ||
pix_fmt == AV_PIX_FMT_MONOBLACK || pix_fmt == AV_PIX_FMT_MONOWHITE;
}
static av_always_inline int isPlanar(enum AVPixelFormat pix_fmt)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
av_assert0(desc);
return (desc->nb_components >= 2 && (desc->flags & AV_PIX_FMT_FLAG_PLANAR));
}
static av_always_inline int isPackedRGB(enum AVPixelFormat pix_fmt)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
av_assert0(desc);
return ((desc->flags & (AV_PIX_FMT_FLAG_PLANAR | AV_PIX_FMT_FLAG_RGB)) == AV_PIX_FMT_FLAG_RGB);
}
static av_always_inline int isPlanarRGB(enum AVPixelFormat pix_fmt)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
av_assert0(desc);
return ((desc->flags & (AV_PIX_FMT_FLAG_PLANAR | AV_PIX_FMT_FLAG_RGB)) ==
(AV_PIX_FMT_FLAG_PLANAR | AV_PIX_FMT_FLAG_RGB));
}
static av_always_inline int usePal(enum AVPixelFormat pix_fmt)
{
switch (pix_fmt) {
case AV_PIX_FMT_PAL8:
case AV_PIX_FMT_BGR4_BYTE:
case AV_PIX_FMT_BGR8:
case AV_PIX_FMT_GRAY8:
case AV_PIX_FMT_RGB4_BYTE:
case AV_PIX_FMT_RGB8:
return 1;
default:
return 0;
}
}
extern const uint64_t ff_dither4[2];
extern const uint64_t ff_dither8[2];
extern const uint8_t ff_dither_2x2_4[3][8];
extern const uint8_t ff_dither_2x2_8[3][8];
extern const uint8_t ff_dither_4x4_16[5][8];
extern const uint8_t ff_dither_8x8_32[9][8];
extern const uint8_t ff_dither_8x8_73[9][8];
extern const uint8_t ff_dither_8x8_128[9][8];
extern const uint8_t ff_dither_8x8_220[9][8];
extern const int32_t ff_yuv2rgb_coeffs[11][4];
extern const AVClass ff_sws_context_class;
/**
* Set c->swscale to an unscaled converter if one exists for the specific
* source and destination formats, bit depths, flags, etc.
*/
void ff_get_unscaled_swscale(SwsContext *c);
void ff_get_unscaled_swscale_ppc(SwsContext *c);
void ff_get_unscaled_swscale_arm(SwsContext *c);
void ff_get_unscaled_swscale_aarch64(SwsContext *c);
/**
* Return function pointer to fastest main scaler path function depending
* on architecture and available optimizations.
*/
SwsFunc ff_getSwsFunc(SwsContext *c);
void ff_sws_init_input_funcs(SwsContext *c);
void ff_sws_init_output_funcs(SwsContext *c,
yuv2planar1_fn *yuv2plane1,
yuv2planarX_fn *yuv2planeX,
yuv2interleavedX_fn *yuv2nv12cX,
yuv2packed1_fn *yuv2packed1,
yuv2packed2_fn *yuv2packed2,
yuv2packedX_fn *yuv2packedX,
yuv2anyX_fn *yuv2anyX);
void ff_sws_init_swscale_ppc(SwsContext *c);
void ff_sws_init_swscale_vsx(SwsContext *c);
void ff_sws_init_swscale_x86(SwsContext *c);
void ff_sws_init_swscale_aarch64(SwsContext *c);
void ff_sws_init_swscale_arm(SwsContext *c);
void ff_hyscale_fast_c(SwsContext *c, int16_t *dst, int dstWidth,
const uint8_t *src, int srcW, int xInc);
void ff_hcscale_fast_c(SwsContext *c, int16_t *dst1, int16_t *dst2,
int dstWidth, const uint8_t *src1,
const uint8_t *src2, int srcW, int xInc);
int ff_init_hscaler_mmxext(int dstW, int xInc, uint8_t *filterCode,
int16_t *filter, int32_t *filterPos,
int numSplits);
void ff_hyscale_fast_mmxext(SwsContext *c, int16_t *dst,
int dstWidth, const uint8_t *src,
int srcW, int xInc);
void ff_hcscale_fast_mmxext(SwsContext *c, int16_t *dst1, int16_t *dst2,
int dstWidth, const uint8_t *src1,
const uint8_t *src2, int srcW, int xInc);
/**
* Allocate and return an SwsContext.
* This is like sws_getContext() but does not perform the init step, allowing
* the user to set additional AVOptions.
*
* @see sws_getContext()
*/
struct SwsContext *sws_alloc_set_opts(int srcW, int srcH, enum AVPixelFormat srcFormat,
int dstW, int dstH, enum AVPixelFormat dstFormat,
int flags, const double *param);
int ff_sws_alphablendaway(SwsContext *c, const uint8_t *src[],
int srcStride[], int srcSliceY, int srcSliceH,
uint8_t *dst[], int dstStride[]);
static inline void fillPlane16(uint8_t *plane, int stride, int width, int height, int y,
int alpha, int bits, const int big_endian)
{
int i, j;
uint8_t *ptr = plane + stride * y;
int v = alpha ? 0xFFFF>>(16-bits) : (1<<(bits-1));
for (i = 0; i < height; i++) {
#define FILL(wfunc) \
for (j = 0; j < width; j++) {\
wfunc(ptr+2*j, v);\
}
if (big_endian) {
FILL(AV_WB16);
} else {
FILL(AV_WL16);
}
ptr += stride;
}
#undef FILL
}
static inline void fillPlane32(uint8_t *plane, int stride, int width, int height, int y,
int alpha, int bits, const int big_endian, int is_float)
{
int i, j;
uint8_t *ptr = plane + stride * y;
uint32_t v;
uint32_t onef32 = 0x3f800000;
if (is_float)
v = alpha ? onef32 : 0;
else
v = alpha ? 0xFFFFFFFF>>(32-bits) : (1<<(bits-1));
for (i = 0; i < height; i++) {
#define FILL(wfunc) \
for (j = 0; j < width; j++) {\
wfunc(ptr+4*j, v);\
}
if (big_endian) {
FILL(AV_WB32);
} else {
FILL(AV_WL32);
}
ptr += stride;
}
#undef FILL
}
#define MAX_SLICE_PLANES 4
/// Slice plane
typedef struct SwsPlane
{
int available_lines; ///< max number of lines that can be hold by this plane
int sliceY; ///< index of first line
int sliceH; ///< number of lines
uint8_t **line; ///< line buffer
uint8_t **tmp; ///< Tmp line buffer used by mmx code
} SwsPlane;
/**
* Struct which defines a slice of an image to be scaled or an output for
* a scaled slice.
* A slice can also be used as intermediate ring buffer for scaling steps.
*/
typedef struct SwsSlice
{
int width; ///< Slice line width
int h_chr_sub_sample; ///< horizontal chroma subsampling factor
int v_chr_sub_sample; ///< vertical chroma subsampling factor
int is_ring; ///< flag to identify if this slice is a ring buffer
int should_free_lines; ///< flag to identify if there are dynamic allocated lines
enum AVPixelFormat fmt; ///< planes pixel format
SwsPlane plane[MAX_SLICE_PLANES]; ///< color planes
} SwsSlice;
/**
* Struct which holds all necessary data for processing a slice.
* A processing step can be a color conversion or horizontal/vertical scaling.
*/
typedef struct SwsFilterDescriptor
{
SwsSlice *src; ///< Source slice
SwsSlice *dst; ///< Output slice
int alpha; ///< Flag for processing alpha channel
void *instance; ///< Filter instance data
/// Function for processing input slice sliceH lines starting from line sliceY
int (*process)(SwsContext *c, struct SwsFilterDescriptor *desc, int sliceY, int sliceH);