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Golang struct_jpeg_compress_struct.err方法代碼示例

本文整理匯總了Golang中C.struct_jpeg_compress_struct.err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.err方法的具體用法?Golang struct_jpeg_compress_struct.err怎麽用?Golang struct_jpeg_compress_struct.err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C.struct_jpeg_compress_struct的用法示例。


在下文中一共展示了struct_jpeg_compress_struct.err方法的1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: 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


注:本文中的C.struct_jpeg_compress_struct.err方法示例由純淨天空整理自Github/MSDocs等開源代碼及文檔管理平台,相關代碼片段篩選自各路編程大神貢獻的開源項目,源碼版權歸原作者所有,傳播和使用請參考對應項目的License;未經允許,請勿轉載。