SkVideoDecoder.cpp File Reference

#include "experimental/ffmpeg/SkVideoDecoder.h"
#include "include/core/SkBitmap.h"
#include "include/core/SkColorSpace.h"
#include "include/core/SkImage.h"
#include "include/core/SkStream.h"
#include "include/core/SkYUVAPixmaps.h"
#include "include/gpu/ganesh/SkImageGanesh.h"

Go to the source code of this file.

Classes
struct	av_transfer_characteristics

Macros
#define	ExpandWP(index)   gWP[index].fX, gWP[index].fY

Enumerations
enum	Whitepoint {   WP_D65 , WP_C , WP_DCI , WP_E ,   WP_NB }

Functions
static SkYUVColorSpace	get_yuvspace (AVColorSpace space)
static skcms_TransferFunction	compute_transfer (AVColorTransferCharacteristic t)
sk_sp< SkColorSpace >	make_colorspace (AVColorPrimaries primaries, AVColorTransferCharacteristic transfer)
static bool	check_err (int err, const int silentList[]=nullptr)
static int	skstream_read_packet (void *ctx, uint8_t *dstBuffer, int dstSize)
static int64_t	skstream_seek_packet (void *ctx, int64_t pos, int whence)
static sk_sp< SkImage >	make_yuv_420 (GrRecordingContext *rContext, int w, int h, uint8_t *const data[], int const strides[], SkYUVColorSpace yuvSpace, sk_sp< SkColorSpace > cs)

Variables
const av_transfer_characteristics	gTransfer [AVCOL_TRC_NB]
const SkPoint	gWP [WP_NB]
const SkColorSpacePrimaries	gPrimaries [AVCOL_PRI_NB]

Macro Definition Documentation

ExpandWP

#define ExpandWP

(

index

)

gWP[index].fX, gWP[index].fY

Definition at line 83 of file SkVideoDecoder.cpp.

Enumeration Type Documentation

Whitepoint

enum Whitepoint

Enumerator
WP_D65
WP_C
WP_DCI
WP_E
WP_NB

Definition at line 68 of file SkVideoDecoder.cpp.

                {
    WP_D65,
    WP_C,
    WP_DCI,
    WP_E,
    WP_NB,
};

Function Documentation

check_err()

static bool check_err ( int  err, const int  silentList[] = nullptr  )

static

Definition at line 116 of file SkVideoDecoder.cpp.

                                                                 {
    if (err >= 0) {
        return false;
    }
 
    if (silentList) {
        for (; *silentList; ++silentList) {
            if (*silentList == err) {
                return true;    // we still report the error, but we don't printf
            }
        }
    }
 
    char errbuf[128];
    const char *errbuf_ptr = errbuf;
 
    if (av_strerror(err, errbuf, sizeof(errbuf)) < 0) {
        errbuf_ptr = strerror(AVUNERROR(err));
    }
    SkDebugf("%s\n", errbuf_ptr);
    return true;
}

compute_transfer()

static skcms_TransferFunction compute_transfer ( AVColorTransferCharacteristic  t )

static

Definition at line 49 of file SkVideoDecoder.cpp.

                                                                                {
    const av_transfer_characteristics* av = &gTransfer[AVCOL_TRC_BT709];
    if ((unsigned)t < AVCOL_TRC_NB) {
        av = &gTransfer[t];
    }
    if (av->alpha == 0) {
        av = &gTransfer[AVCOL_TRC_BT709];
    }
 
    skcms_TransferFunction linear_to_encoded = {
        av->gamma, std::pow(av->alpha, 1/av->gamma), 0, av->delta, av->beta, 1 - av->alpha, 0,
    };
    skcms_TransferFunction encoded_to_linear;
    bool success = skcms_TransferFunction_invert(&linear_to_encoded, &encoded_to_linear);
    SkASSERT(success);
 
    return encoded_to_linear;
}

get_yuvspace()

static SkYUVColorSpace get_yuvspace ( AVColorSpace  space )

static

Definition at line 16 of file SkVideoDecoder.cpp.

                                                        {
    // this is pretty incomplete -- TODO: look to convert more AVColorSpaces
    switch (space) {
        case AVCOL_SPC_RGB:     return kIdentity_SkYUVColorSpace;
        case AVCOL_SPC_BT709:   return kRec709_SkYUVColorSpace;
        case AVCOL_SPC_SMPTE170M:
        case AVCOL_SPC_SMPTE240M:
        case AVCOL_SPC_BT470BG: return kRec601_SkYUVColorSpace;
        default: break;
    }
    return kRec709_SkYUVColorSpace;
}

make_colorspace()

sk_sp< SkColorSpace > make_colorspace	(	AVColorPrimaries	primaries,
		AVColorTransferCharacteristic	transfer
	)

Definition at line 99 of file SkVideoDecoder.cpp.

                                                                            {
    if (primaries == AVCOL_PRI_BT709 && transfer == AVCOL_TRC_BT709) {
        return SkColorSpace::MakeSRGB();
    }
 
    const SkColorSpacePrimaries* p = &gPrimaries[0];
    if ((unsigned)primaries < (unsigned)AVCOL_PRI_NB) {
        p = &gPrimaries[primaries];
    }
 
    skcms_Matrix3x3 matrix;
    p->toXYZD50(&matrix);
    return SkColorSpace::MakeRGB(compute_transfer(transfer), matrix);
}

make_yuv_420()

static sk_sp< SkImage > make_yuv_420 ( GrRecordingContext *  rContext, int  w, int  h, uint8_t *const  data[], int const  strides[], SkYUVColorSpace  yuvSpace, sk_sp< SkColorSpace >  cs  )

static

Definition at line 165 of file SkVideoDecoder.cpp.

                                                           {
    SkYUVAInfo yuvaInfo({w, h},
                        SkYUVAInfo::PlaneConfig::kY_U_V,
                        SkYUVAInfo::Subsampling::k420,
                        yuvSpace);
    SkPixmap pixmaps[3];
    pixmaps[0].reset(SkImageInfo::MakeA8(w, h), data[0], strides[0]);
    w = (w + 1)/2;
    h = (h + 1)/2;
    pixmaps[1].reset(SkImageInfo::MakeA8(w, h), data[1], strides[1]);
    pixmaps[2].reset(SkImageInfo::MakeA8(w, h), data[2], strides[2]);
    auto yuvaPixmaps = SkYUVAPixmaps::FromExternalPixmaps(yuvaInfo, pixmaps);
 
    return SkImages::TextureFromYUVAPixmaps(
            rContext, yuvaPixmaps, skgpu::Mipmapped::kNo, false, std::move(cs));
}

skstream_read_packet()

static int skstream_read_packet ( void *  ctx, uint8_t *  dstBuffer, int  dstSize  )

static

Definition at line 139 of file SkVideoDecoder.cpp.

                                                                            {
    SkStream* stream = (SkStream*)ctx;
    int result = (int)stream->read(dstBuffer, dstSize);
    if (result == 0) {
        result = AVERROR_EOF;
    }
    return result;
}

skstream_seek_packet()

static int64_t skstream_seek_packet ( void *  ctx, int64_t  pos, int  whence  )

static

Definition at line 148 of file SkVideoDecoder.cpp.

                                                                        {
    SkStream* stream = (SkStream*)ctx;
    switch (whence) {
        case SEEK_SET:
            break;
        case SEEK_CUR:
            pos = (int64_t)stream->getPosition() + pos;
            break;
        case SEEK_END:
            pos = (int64_t)stream->getLength() + pos;
            break;
        default:
            return -1;
    }
    return stream->seek(SkToSizeT(pos)) ? pos : -1;
}

Variable Documentation

gPrimaries

const SkColorSpacePrimaries gPrimaries[AVCOL_PRI_NB]

Initial value:

= {
    [AVCOL_PRI_BT709]     = { 0.640f, 0.330f, 0.300f, 0.600f, 0.150f, 0.060f, ExpandWP(WP_D65) },
    [AVCOL_PRI_BT470M]    = { 0.670f, 0.330f, 0.210f, 0.710f, 0.140f, 0.080f, ExpandWP(WP_C)   },
    [AVCOL_PRI_BT470BG]   = { 0.640f, 0.330f, 0.290f, 0.600f, 0.150f, 0.060f, ExpandWP(WP_D65) },
    [AVCOL_PRI_SMPTE170M] = { 0.630f, 0.340f, 0.310f, 0.595f, 0.155f, 0.070f, ExpandWP(WP_D65) },
    [AVCOL_PRI_SMPTE240M] = { 0.630f, 0.340f, 0.310f, 0.595f, 0.155f, 0.070f, ExpandWP(WP_D65) },
    [AVCOL_PRI_SMPTE428]  = { 0.735f, 0.265f, 0.274f, 0.718f, 0.167f, 0.009f, ExpandWP(WP_E)   },
    [AVCOL_PRI_SMPTE431]  = { 0.680f, 0.320f, 0.265f, 0.690f, 0.150f, 0.060f, ExpandWP(WP_DCI) },
    [AVCOL_PRI_SMPTE432]  = { 0.680f, 0.320f, 0.265f, 0.690f, 0.150f, 0.060f, ExpandWP(WP_D65) },
    [AVCOL_PRI_FILM]      = { 0.681f, 0.319f, 0.243f, 0.692f, 0.145f, 0.049f, ExpandWP(WP_C)   },
    [AVCOL_PRI_BT2020]    = { 0.708f, 0.292f, 0.170f, 0.797f, 0.131f, 0.046f, ExpandWP(WP_D65) },
    [AVCOL_PRI_JEDEC_P22] = { 0.630f, 0.340f, 0.295f, 0.605f, 0.155f, 0.077f, ExpandWP(WP_D65) },
}

Definition at line 85 of file SkVideoDecoder.cpp.

gTransfer

const av_transfer_characteristics gTransfer[AVCOL_TRC_NB]

Initial value:

= {
    [AVCOL_TRC_BT709]     = { 1.099,  0.018,  0.45, 4.5 },
    [AVCOL_TRC_GAMMA22]   = { 1.0,    0.0,    1.0 / 2.2, 0.0 },
    [AVCOL_TRC_GAMMA28]   = { 1.0,    0.0,    1.0 / 2.8, 0.0 },
    [AVCOL_TRC_SMPTE170M] = { 1.099,  0.018,  0.45, 4.5 },
    [AVCOL_TRC_SMPTE240M] = { 1.1115, 0.0228, 0.45, 4.0 },
    [AVCOL_TRC_IEC61966_2_1] = { 1.055, 0.0031308, 1.0 / 2.4, 12.92 },
    [AVCOL_TRC_IEC61966_2_4] = { 1.099, 0.018, 0.45, 4.5 },
    [AVCOL_TRC_BT2020_10] = { 1.099,  0.018,  0.45, 4.5 },
    [AVCOL_TRC_BT2020_12] = { 1.0993, 0.0181, 0.45, 4.5 },
}

Definition at line 37 of file SkVideoDecoder.cpp.

gWP

const SkPoint gWP[WP_NB]

Initial value:

= {
    [WP_D65] = { 0.3127f, 0.3290f },
    [WP_C]   = { 0.3100f, 0.3160f },
    [WP_DCI] = { 0.3140f, 0.3510f },
    [WP_E]   = { 1/3.0f, 1/3.0f },
}

Definition at line 76 of file SkVideoDecoder.cpp.