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Golang struct_jpeg_compress_struct.image_height方法代碼示例

本文整理匯總了Golang中C.struct_jpeg_compress_struct.image_height方法的典型用法代碼示例。如果您正苦於以下問題：Golang struct_jpeg_compress_struct.image_height方法的具體用法？Golang struct_jpeg_compress_struct.image_height怎麽用？Golang struct_jpeg_compress_struct.image_height使用的例子？那麽, 這裏精選的方法代碼示例或許可以為您提供幫助。您也可以進一步了解該方法所在類C.struct_jpeg_compress_struct的用法示例。


在下文中一共展示了struct_jpeg_compress_struct.image_height方法的5個代碼示例，這些例子默認根據受歡迎程度排序。您可以為喜歡或者感覺有用的代碼點讚，您的評價將有助於係統推薦出更棒的Golang代碼示例。

示例1: encodeYCbCr

// encode image.YCbCr
func encodeYCbCr(cinfo *C.struct_jpeg_compress_struct, src *image.YCbCr, p *EncoderOptions) (err error) {
	// Set up compression parameters
	cinfo.image_width = C.JDIMENSION(src.Bounds().Dx())
	cinfo.image_height = C.JDIMENSION(src.Bounds().Dy())
	cinfo.input_components = 3
	cinfo.in_color_space = C.JCS_YCbCr

	C.jpeg_set_defaults(cinfo)
	setupEncoderOptions(cinfo, p)

	compInfo := (*[3]C.jpeg_component_info)(unsafe.Pointer(cinfo.comp_info))
	colorVDiv := 1
	switch src.SubsampleRatio {
	case image.YCbCrSubsampleRatio444:
		// 1x1,1x1,1x1
		compInfo[Y].h_samp_factor, compInfo[Y].v_samp_factor = 1, 1
		compInfo[Cb].h_samp_factor, compInfo[Cb].v_samp_factor = 1, 1
		compInfo[Cr].h_samp_factor, compInfo[Cr].v_samp_factor = 1, 1
	case image.YCbCrSubsampleRatio440:
		// 1x2,1x1,1x1
		compInfo[Y].h_samp_factor, compInfo[Y].v_samp_factor = 1, 2
		compInfo[Cb].h_samp_factor, compInfo[Cb].v_samp_factor = 1, 1
		compInfo[Cr].h_samp_factor, compInfo[Cr].v_samp_factor = 1, 1
		colorVDiv = 2
	case image.YCbCrSubsampleRatio422:
		// 2x1,1x1,1x1
		compInfo[Y].h_samp_factor, compInfo[Y].v_samp_factor = 2, 1
		compInfo[Cb].h_samp_factor, compInfo[Cb].v_samp_factor = 1, 1
		compInfo[Cr].h_samp_factor, compInfo[Cr].v_samp_factor = 1, 1
	case image.YCbCrSubsampleRatio420:
		// 2x2,1x1,1x1
		compInfo[Y].h_samp_factor, compInfo[Y].v_samp_factor = 2, 2
		compInfo[Cb].h_samp_factor, compInfo[Cb].v_samp_factor = 1, 1
		compInfo[Cr].h_samp_factor, compInfo[Cr].v_samp_factor = 1, 1
		colorVDiv = 2
	}

	// libjpeg raw data in is in planar format, which avoids unnecessary
	// planar->packed->planar conversions.
	cinfo.raw_data_in = C.TRUE

	// Start compression
	C.jpeg_start_compress(cinfo, C.TRUE)
	C.encode_ycbcr(
		cinfo,
		C.JSAMPROW(unsafe.Pointer(&src.Y[0])),
		C.JSAMPROW(unsafe.Pointer(&src.Cb[0])),
		C.JSAMPROW(unsafe.Pointer(&src.Cr[0])),
		C.int(src.YStride),
		C.int(src.CStride),
		C.int(colorVDiv),
	)
	C.jpeg_finish_compress(cinfo)
	return
}
開發者ID:ieee0824，項目名稱:go-libjpeg，代碼行數:56，代碼來源:compress.go

示例2: Encode

func Encode(w io.Writer, m image.Image, o *Options) error {
	quality := 75
	if o != nil {
		quality = o.Quality
	}

	var cinfo C.struct_jpeg_compress_struct
	var jerr C.struct_jpeg_error_mgr
	var workBuf *C.uchar
	var workBufLen C.ulong

	cinfo.err = C.jpeg_std_error(&jerr)
	C.jpeg_CreateCompress(&cinfo, C.JPEG_LIB_VERSION, C.size_t(unsafe.Sizeof(cinfo)))
	C.jpeg_mem_dest(&cinfo, &workBuf, &workBufLen)

	bounds := m.Bounds()
	cinfo.image_width = C.JDIMENSION(bounds.Dx())
	cinfo.image_height = C.JDIMENSION(bounds.Dy())
	cinfo.input_components = 3
	cinfo.in_color_space = C.JCS_RGB

	C.jpeg_set_defaults(&cinfo)
	C.jpeg_set_quality(&cinfo, C.int(quality), C.boolean(1))
	C.jpeg_start_compress(&cinfo, C.boolean(1))

	rowBuf := make([]byte, cinfo.image_width*3)

	for cinfo.next_scanline < cinfo.image_height {
		for x := 0; x < int(cinfo.image_width); x += 1 {
			r, g, b, _ := m.At(x, int(cinfo.next_scanline)).RGBA()
			rowBuf[x*3] = byte(r >> 8)
			rowBuf[x*3+1] = byte(g >> 8)
			rowBuf[x*3+2] = byte(b >> 8)
		}

		rowPointer := C.JSAMPROW(unsafe.Pointer(&rowBuf[0]))
		C.jpeg_write_scanlines(&cinfo, &rowPointer, 1)
	}

	C.jpeg_finish_compress(&cinfo)
	C.jpeg_destroy_compress(&cinfo)

	outBs := C.GoBytes(unsafe.Pointer(workBuf), C.int(workBufLen))
	w.Write(outBs)
	C.free(unsafe.Pointer(workBuf))

	return nil
}
開發者ID:lye，項目名稱:libjpeg，代碼行數:48，代碼來源:encode.go

示例3: encodeGray

// encode image.Gray
func encodeGray(cinfo *C.struct_jpeg_compress_struct, src *image.Gray, p *EncoderOptions) (err error) {
	// Set up compression parameters
	cinfo.image_width = C.JDIMENSION(src.Bounds().Dx())
	cinfo.image_height = C.JDIMENSION(src.Bounds().Dy())
	cinfo.input_components = 1
	cinfo.in_color_space = C.JCS_GRAYSCALE

	C.jpeg_set_defaults(cinfo)
	setupEncoderOptions(cinfo, p)

	compInfo := (*C.jpeg_component_info)(unsafe.Pointer(cinfo.comp_info))
	compInfo.h_samp_factor, compInfo.v_samp_factor = 1, 1

	// libjpeg raw data in is in planar format, which avoids unnecessary
	// planar->packed->planar conversions.
	cinfo.raw_data_in = C.TRUE

	// Start compression
	C.jpeg_start_compress(cinfo, C.TRUE)

	// Allocate JSAMPIMAGE to hold pointers to one iMCU worth of image data
	// this is a safe overestimate; we use the return value from
	// jpeg_read_raw_data to figure out what is the actual iMCU row count.
	var rowPtr [AlignSize]C.JSAMPROW
	arrayPtr := [1]C.JSAMPARRAY{
		C.JSAMPARRAY(unsafe.Pointer(&rowPtr[0])),
	}

	var rows C.JDIMENSION
	for rows = 0; rows < cinfo.image_height; {
		// First fill in the pointers into the plane data buffers
		for j := 0; j < int(C.DCTSIZE*compInfo.v_samp_factor); j++ {
			rowPtr[j] = C.JSAMPROW(unsafe.Pointer(&src.Pix[src.Stride*(int(rows)+j)]))
		}
		// Get the data
		rows += C.jpeg_write_raw_data(cinfo, C.JSAMPIMAGE(unsafe.Pointer(&arrayPtr[0])), C.JDIMENSION(C.DCTSIZE*compInfo.v_samp_factor))
	}

	C.jpeg_finish_compress(cinfo)
	return
}
開發者ID:edvakf，項目名稱:go-libjpeg，代碼行數:42，代碼來源:compress.go

示例4: encodeGray

// encode image.Gray
func encodeGray(cinfo *C.struct_jpeg_compress_struct, src *image.Gray, p *EncoderOptions) (err error) {
	// Set up compression parameters
	cinfo.image_width = C.JDIMENSION(src.Bounds().Dx())
	cinfo.image_height = C.JDIMENSION(src.Bounds().Dy())
	cinfo.input_components = 1
	cinfo.in_color_space = C.JCS_GRAYSCALE

	C.jpeg_set_defaults(cinfo)
	setupEncoderOptions(cinfo, p)

	compInfo := (*C.jpeg_component_info)(unsafe.Pointer(cinfo.comp_info))
	compInfo.h_samp_factor, compInfo.v_samp_factor = 1, 1

	// libjpeg raw data in is in planar format, which avoids unnecessary
	// planar->packed->planar conversions.
	cinfo.raw_data_in = C.TRUE

	// Start compression
	C.jpeg_start_compress(cinfo, C.TRUE)
	C.encode_gray(cinfo, C.JSAMPROW(unsafe.Pointer(&src.Pix[0])), C.int(src.Stride))
	C.jpeg_finish_compress(cinfo)
	return
}
開發者ID:ieee0824，項目名稱:go-libjpeg，代碼行數:24，代碼來源:compress.go

示例5: encodeYCbCr

// encode image.YCbCr
func encodeYCbCr(cinfo *C.struct_jpeg_compress_struct, src *image.YCbCr, p *EncoderOptions) (err error) {
	// Set up compression parameters
	cinfo.image_width = C.JDIMENSION(src.Bounds().Dx())
	cinfo.image_height = C.JDIMENSION(src.Bounds().Dy())
	cinfo.input_components = 3
	cinfo.in_color_space = C.JCS_YCbCr

	C.jpeg_set_defaults(cinfo)
	setupEncoderOptions(cinfo, p)

	compInfo := (*[3]C.jpeg_component_info)(unsafe.Pointer(cinfo.comp_info))
	colorVDiv := 1
	switch src.SubsampleRatio {
	case image.YCbCrSubsampleRatio444:
		// 1x1,1x1,1x1
		compInfo[Y].h_samp_factor, compInfo[Y].v_samp_factor = 1, 1
		compInfo[Cb].h_samp_factor, compInfo[Cb].v_samp_factor = 1, 1
		compInfo[Cr].h_samp_factor, compInfo[Cr].v_samp_factor = 1, 1
	case image.YCbCrSubsampleRatio440:
		// 1x2,1x1,1x1
		compInfo[Y].h_samp_factor, compInfo[Y].v_samp_factor = 1, 2
		compInfo[Cb].h_samp_factor, compInfo[Cb].v_samp_factor = 1, 1
		compInfo[Cr].h_samp_factor, compInfo[Cr].v_samp_factor = 1, 1
		colorVDiv = 2
	case image.YCbCrSubsampleRatio422:
		// 2x1,1x1,1x1
		compInfo[Y].h_samp_factor, compInfo[Y].v_samp_factor = 2, 1
		compInfo[Cb].h_samp_factor, compInfo[Cb].v_samp_factor = 1, 1
		compInfo[Cr].h_samp_factor, compInfo[Cr].v_samp_factor = 1, 1
	case image.YCbCrSubsampleRatio420:
		// 2x2,1x1,1x1
		compInfo[Y].h_samp_factor, compInfo[Y].v_samp_factor = 2, 2
		compInfo[Cb].h_samp_factor, compInfo[Cb].v_samp_factor = 1, 1
		compInfo[Cr].h_samp_factor, compInfo[Cr].v_samp_factor = 1, 1
		colorVDiv = 2
	}

	// libjpeg raw data in is in planar format, which avoids unnecessary
	// planar->packed->planar conversions.
	cinfo.raw_data_in = C.TRUE

	// Start compression
	C.jpeg_start_compress(cinfo, C.TRUE)

	// Allocate JSAMPIMAGE to hold pointers to one iMCU worth of image data
	// this is a safe overestimate; we use the return value from
	// jpeg_read_raw_data to figure out what is the actual iMCU row count.
	var yRowPtr [AlignSize]C.JSAMPROW
	var cbRowPtr [AlignSize]C.JSAMPROW
	var crRowPtr [AlignSize]C.JSAMPROW
	yCbCrPtr := [3]C.JSAMPARRAY{
		C.JSAMPARRAY(unsafe.Pointer(&yRowPtr[0])),
		C.JSAMPARRAY(unsafe.Pointer(&cbRowPtr[0])),
		C.JSAMPARRAY(unsafe.Pointer(&crRowPtr[0])),
	}

	var rows C.JDIMENSION
	for rows = 0; rows < cinfo.image_height; {
		// First fill in the pointers into the plane data buffers
		for j := 0; j < int(C.DCTSIZE*compInfo[Y].v_samp_factor); j++ {
			yRowPtr[j] = C.JSAMPROW(unsafe.Pointer(&src.Y[src.YStride*(int(rows)+j)]))
		}
		for j := 0; j < int(C.DCTSIZE*compInfo[Cb].v_samp_factor); j++ {
			cbRowPtr[j] = C.JSAMPROW(unsafe.Pointer(&src.Cb[src.CStride*(int(rows)/colorVDiv+j)]))
			crRowPtr[j] = C.JSAMPROW(unsafe.Pointer(&src.Cr[src.CStride*(int(rows)/colorVDiv+j)]))
		}
		// Get the data
		rows += C.jpeg_write_raw_data(cinfo, C.JSAMPIMAGE(unsafe.Pointer(&yCbCrPtr[0])), C.JDIMENSION(C.DCTSIZE*compInfo[0].v_samp_factor))
	}

	C.jpeg_finish_compress(cinfo)
	return
}
開發者ID:edvakf，項目名稱:go-libjpeg，代碼行數:74，代碼來源:compress.go


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