perf(性能优化): 优化资源读写与字体图像处理

ofdgo_editor_images.go

@@ -42,9 +42,16 @@ type ImagePageOptions struct {
 	OnProgress    func(stage string, completed, total int) error
 }
 
+// editorImagePageInfo 保存同批次已校验图片的建页信息，不持有编码、像素或颜色模型
+type editorImagePageInfo struct {
+	size     image.Point
+	format   string
+	metadata baseimage.PageInfo
+}
+
 // ImportImages 将PNG、JPEG、BMP、单页TIFF或JBIG2逐张建页并插入指定位置，一次操作计入一条撤销记录
 // 保留像素及透明度，方向通过对象变换实现，不重新采样；图片压缩沿用AddImage规则
-// 同一批次的相同图片复用解码校验结果，不额外保留像素数据
+// 同一批次的相同图片复用解码校验及元数据，不额外保留像素数据
 // 失败或取消时不修改文档，读取期间仍需容纳单张图片的解码数据
 // 入参: ctx 取消上下文, sources 按页面顺序排列的图片, at 插入位置, options 建页选项
 // 返回: error 错误信息
@@ -82,7 +89,7 @@ func (e *Editor) ImportImages(ctx context.Context, sources []ImagePageSource, at
 	}
 	return e.Transaction(func(e *Editor) error {
 		indexes := make([]int, 0, len(sources))
-		verified := make(map[[32]byte]bool)
+		verified := make(map[[32]byte]editorImagePageInfo)
 		for i, source := range sources {
 			if err := ctx.Err(); err != nil {
 				return err
@@ -111,33 +118,36 @@ func (e *Editor) ImportImages(ctx context.Context, sources []ImagePageSource, at
 }
 
 // addImagePage 保留原图并按方向、物理尺寸与纸张选项建页
-// 入参: ctx 取消上下文, data 图片数据, options 建页选项, verified 本批次已成功解码的图片摘要
+// 入参: ctx 取消上下文, data 图片数据, options 建页选项, verified 本批次已校验图片的建页信息
 // 返回: int 从0开始的页面索引, error 错误信息
-func (e *Editor) addImagePage(ctx context.Context, data []byte, options ImagePageOptions, verified map[[32]byte]bool) (int, error) {
+func (e *Editor) addImagePage(ctx context.Context, data []byte, options ImagePageOptions, verified map[[32]byte]editorImagePageInfo) (int, error) {
 	if err := ctx.Err(); err != nil {
 		return 0, err
 	}
-	config, format, err := baseimage.DecodeConfigDataContext(ctx, data)
-	if err != nil {
-		return 0, err
-	}
-	if format != "png" && format != "jpeg" && format != "bmp" && format != "tiff" && format != "jbig2" {
-		return 0, fmt.Errorf("only PNG, JPEG, BMP, single-page TIFF and JBIG2 images are supported")
-	}
 	var decoded image.Image
 	checksum := sha256.Sum256(data)
-	if !verified[checksum] {
+	info, known := verified[checksum]
+	if !known {
+		config, format, err := baseimage.DecodeConfigDataContext(ctx, data)
+		if err != nil {
+			return 0, err
+		}
+		if format != "png" && format != "jpeg" && format != "bmp" && format != "tiff" && format != "jbig2" {
+			return 0, fmt.Errorf("only PNG, JPEG, BMP, single-page TIFF and JBIG2 images are supported")
+		}
 		decoded, _, err = baseimage.DecodePixelsContext(ctx, data)
 		if err != nil {
 			return 0, err
 		}
-		verified[checksum] = true
+		metadata, err := baseimage.PageMetadataContext(ctx, data, format, options.DPI)
+		if err != nil {
+			return 0, err
+		}
+		info = editorImagePageInfo{size: image.Pt(config.Width, config.Height), format: format, metadata: metadata}
+		verified[checksum] = info
 	}
-	metadata, err := baseimage.PageMetadataContext(ctx, data, format, options.DPI)
-	if err != nil {
-		return 0, err
-	}
-	w, h := float64(config.Width)*25.4/metadata.XDPI, float64(config.Height)*25.4/metadata.YDPI
+	metadata := info.metadata
+	w, h := float64(info.size.X)*25.4/metadata.XDPI, float64(info.size.Y)*25.4/metadata.YDPI
 	if metadata.Orientation >= 5 {
 		w, h = h, w
 	}
@@ -154,7 +164,7 @@ func (e *Editor) addImagePage(ctx context.Context, data []byte, options ImagePag
 	if err := ctx.Err(); err != nil {
 		return 0, err
 	}
-	resource, err := e.addImage(data, config, format, decoded)
+	resource, err := e.addImage(ctx, data, info.size, info.format, decoded, checksum)
 	if err != nil {
 		return 0, err
 	}