使用ImageIO 在Java 中調整JPEG 壓縮等級

在影像處理領域，控制JPEG 檔案的壓縮等級對於平衡至關重要影像品質和文件大小。雖然 ImageIO 的預設壓縮等級可能並不總是足夠，但本文將深入研究如何微調此參數。

ImageWriter jpgWriter = ImageIO.getImageWritersByFormatName("jpg").next();

ImageWriter jpgWriter = Image .next();

ImageWriteParam jpgWriteParam = jpgWriter.getDefaultWriteParam();
jpgWriteParam.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);

ImageWriteParam jpgWriteParam = jpgWriter.getDefaultWriteParam(); jpgWriteParam.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);

jpgWriteParam.setCompressionQuality(0.7f); // Set a compression quality of 70%

jpgWriteParam.setCompressionQuality(0.7f); // 設定壓縮品質為70%

ImageOutputStream outputStream = createOutputStream(); // Generate an OutputStream (e.g., a FileImageOutputStream)
jpgWriter.setOutput(outputStream);

ImageOutputStream輸出流= 建立輸出流(); // 產生一個OutputStream（例如FileImageOutputStream） jpgWriter.setOutput(outputStream);

jpgWriter.dispose();

jpgWriter. dispose ();

總之，透過直接取得ImageWriter並設定明確的壓縮參數，您可以精確控制JPEG壓縮級別，根據您的特定要求優化影像品質和檔案大小。