Especifique o parâmetro sharpen para aplicar nitidez a uma imagem armazenada no Object Storage Service (OSS). Este tópico descreve o parâmetro sharpen usado para aumentar a nitidez de uma imagem e fornece exemplos de aplicação.
Parâmetros
Ação: sharpen
A tabela a seguir descreve os valores válidos para o parâmetro sharpen.
|
Formato |
Descrição |
Valor válido |
|
[value] |
Grau de nitidez. |
[50.399] Valores maiores resultam em imagens mais nítidas. Contudo, valores excessivamente altos podem causar artefatos visuais. Recomendamos definir este parâmetro como 100 para obter resultados ideais. |
Métodos
Aplicar nitidez em uma imagem com leitura pública ou leitura/gravação pública
Esta seção apresenta exemplos de aplicação de nitidez na imagem example.jpg, armazenada no bucket oss-console-img-demo-cn-hangzhou na região China (Hangzhou). A imagem está hospedada na seguinte URL:
https://oss-console-img-demo-cn-hangzhou.oss-cn-hangzhou.aliyuncs.com/example.jpg
Aplique nitidez à imagem original com grau definido como 100. Use a seguinte URL para processar a imagem: https://oss-console-img-demo-cn-hangzhou.oss-cn-hangzhou.aliyuncs.com/example.jpg?x-oss-process=image/sharpen,100.
Aplicar nitidez em uma imagem privada
Use os SDKs do OSS ou a API do OSS para aplicar nitidez a uma imagem privada.
Usar SDKs do OSS
Os exemplos de código a seguir demonstram como aplicar nitidez a uma imagem privada usando os SDKs do OSS nas linguagens de programação mais comuns. Para informações sobre esse processo em outras linguagens, consulte Referências dos SDKs.
Java
É necessário usar o OSS SDK for Java versão 3.17.4 ou posterior.
import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.GetObjectRequest;
import java.io.File;
public class Demo {
public static void main(String[] args) throws Throwable {
// In this example, the endpoint of the China (Hangzhou) region is used. Specify your actual endpoint.
String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
// Specify the region of the bucket in which the private image is stored. Example: cn-hangzhou.
String region = "cn-hangzhou";
// Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured.
EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
// Specify the name of the bucket. Example: examplebucket.
String bucketName = "examplebucket";
// Specify the full path of the object. Do not include the bucket name in the full path.
String objectName = "example.jpg";
// Specify the full path of the processed image. Example: D:\\dest.jpg. If an image that has the same name already exists in the path, the processed image overwrites the image. Otherwise, the processed image is saved in the path.
String pathName = "D:\\dest.jpg";
// Create an OSSClient instance.
// Call the shutdown method to release resources when the OSSClient is no longer in use.
ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);
OSS ossClient = OSSClientBuilder.create()
.endpoint(endpoint)
.credentialsProvider(credentialsProvider)
.clientConfiguration(clientBuilderConfiguration)
.region(region)
.build();
try {
// Specify the degree of sharpness.
String image = "image/sharpen,100";
GetObjectRequest request = new GetObjectRequest(bucketName, objectName);
request.setProcess(image);
// Set the name of the processed image to dest.jpg and save it to your local computer.
// If you specify only the name of the processed image such as dest.jpg without specifying the local path, the processed image is saved to the local path of the project to which the sample program belongs.
ossClient.getObject(request, new File("D:\\dest.jpg"));
} catch (OSSException oe) {
System.out.println("Caught an OSSException, which means your request made it to OSS, "
+ "but was rejected with an error response for some reason.");
System.out.println("Error Message:" + oe.getErrorMessage());
System.out.println("Error Code:" + oe.getErrorCode());
System.out.println("Request ID:" + oe.getRequestId());
System.out.println("Host ID:" + oe.getHostId());
} catch (ClientException ce) {
System.out.println("Caught an ClientException, which means the client encountered "
+ "a serious internal problem while trying to communicate with OSS, "
+ "such as not being able to access the network.");
System.out.println("Error Message:" + ce.getMessage());
} finally {
if (ossClient != null) {
ossClient.shutdown();
}
}
}
}
PHP
É necessário usar o OSS SDK for PHP versão 2.7.0 ou posterior.
<?php
if (is_file(__DIR__ . '/../autoload.php')) {
require_once __DIR__ . '/../autoload.php';
}
if (is_file(__DIR__ . '/../vendor/autoload.php')) {
require_once __DIR__ . '/../vendor/autoload.php';
}
use OSS\Credentials\EnvironmentVariableCredentialsProvider;
use OSS\OssClient;
// Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured.
$provider = new EnvironmentVariableCredentialsProvider();
// Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com.
$endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
// Specify the name of the bucket. Example: examplebucket.
$bucket= "examplebucket";
// Specify the full path of the object. Do not include the bucket name in the full path.
$object = "example.jpg";
// Specify the full path of the processed image. Example: D:\\dest.jpg. If an image that has the same name already exists in the path, the processed image overwrites the image. Otherwise, the processed image is saved in the path.
// If you specify only the name of the processed image such as dest.jpg without specifying the local path, the processed image is saved to the local path of the project to which the sample program belongs.
$download_file = "D:\\dest.jpg";
$config = array(
"provider" => $provider,
"endpoint" => $endpoint,
"signatureVersion" => OssClient::OSS_SIGNATURE_VERSION_V4,
// Specify the ID of the Alibaba Cloud region in which the bucket is located.
"region" => "cn-hangzhou"
);
$ossClient = new OssClient($config);
// Specify the degree of sharpness.
$image = "image/sharpen,100";
$options = array(
OssClient::OSS_FILE_DOWNLOAD => $download_file,
OssClient::OSS_PROCESS => $image);
// Save the processed image to your local computer.
$ossClient->getObject($bucket, $object, $options);
Python
É necessário usar o OSS SDK for Python versão 2.18.4 ou posterior.
# -*- coding: utf-8 -*-
import oss2
from oss2.credentials import EnvironmentVariableCredentialsProvider
# Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured.
auth = oss2.ProviderAuthV4(EnvironmentVariableCredentialsProvider())
# Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com.
# Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com.
endpoint = 'https://oss-cn-hangzhou.aliyuncs.com'
# Specify the ID of the Alibaba Cloud region in which the bucket is located.
region = 'cn-hangzhou'
bucket = oss2.Bucket(auth, endpoint, 'examplebucket', region=region)
# Specify the name of the source image. If the image is not stored in the root directory of the bucket, you must include the full path of the image. Example: exampledir/src.gif.
key = 'example.jpg'
# Specify the name of the processed image.
new_pic = 'D:\\dest.jpg'
# Specify the degree of sharpness.
image = 'image/sharpen,100'
bucket.get_object_to_file(key, new_pic, process=image)
Go
É necessário usar o OSS SDK for Go versão 3.0.2 ou posterior.
package main
import (
"fmt"
"os"
"github.com/aliyun/aliyun-oss-go-sdk/oss"
)
func HandleError(err error) {
fmt.Println("Error:", err)
os.Exit(-1)
}
func main() {
// Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured.
provider, err := oss.NewEnvironmentVariableCredentialsProvider()
if err != nil {
fmt.Println("Error:", err)
os.Exit(-1)
}
// Create an OSSClient instance.
// Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com. Specify your actual endpoint.
client, err := oss.New("https://oss-cn-hangzhou.aliyuncs.com", "", "", oss.SetCredentialsProvider(&provider), oss.AuthVersion(oss.AuthV4), oss.Region("cn-hangzhou"))
if err != nil {
HandleError(err)
}
// Specify the name of the bucket in which the source image is stored. Example: examplebucket.
bucketName := "examplebucket"
bucket, err := client.Bucket(bucketName)
if err != nil {
HandleError(err)
}
// Specify the name of the source image. If the image is not stored in the root directory of the bucket, you must include the full path of the image. Example: exampledir/src.gif.
sourceImageName := "example.jpg"
// Specify the name of the processed image.
targetImageName := "D://dest.jpg"
// Specify the degree of sharpness.
image := "image/sharpen,100"
err = bucket.GetObjectToFile(sourceImageName, targetImageName, oss.Process(image))
if err != nil {
HandleError(err)
}
}
Usar a API RESTful
Se seu cenário exigir alto nível de personalização, chame diretamente as APIs RESTful. Para isso, inclua o cálculo da assinatura no código. Para mais detalhes, consulte (Recomendado) Incluir uma assinatura V4.
Defina o parâmetro sharpen na operação GetObject para aplicar nitidez a uma imagem privada.
GET /oss.jpg?x-oss-process=image/sharpen,100 HTTP/1.1
Host: oss-example.oss-cn-hangzhou.aliyuncs.com
Date: Fri, 28 Oct 2022 06:40:10 GMT
Authorization: OSS4-HMAC-SHA256 Credential=LTAI********************/20250417/cn-hangzhou/oss/aliyun_v4_request,Signature=a7c3554c729d71929e0b84489addee6b2e8d5cb48595adfc51868c299c0c218e