Image Processing (IMG) は、Object Storage service (OSS) によって提供され、大量の画像を処理するために使用できる、安全で費用対効果の高い信頼性の高い画像処理サービスです。 ソース画像をOSSにアップロードした後、RESTful APIを呼び出して、いつでもどこでもインターネット経由で接続されているデバイスで画像を処理できます。
使用上の注意
このトピックでは、中国 (杭州) リージョンのパブリックエンドポイントを使用します。 OSSと同じリージョンにある他のAlibaba CloudサービスからOSSにアクセスする場合は、内部エンドポイントを使用します。 OSSリージョンとエンドポイントの詳細については、「リージョンとエンドポイント」をご参照ください。
このトピックでは、OSSエンドポイントを使用してOSSClientインスタンスを作成します。 カスタムドメイン名またはSTS (Security Token Service) を使用してOSSClientインスタンスを作成する場合は、「初期化」をご参照ください。
IMGパラメータを使用した画像処理
単一のIMGパラメータを使用して画像を処理し、その画像をローカルコンピュータに保存する
#include "oss_api.h"
#include "aos_http_io.h"
/* 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. */
const char *endpoint = "yourEndpoint";
/* Specify the name of the bucket. Example: examplebucket. */
const char *bucket_name = "examplebucket";
/* Specify the full path of the object. Do not include the bucket name in the full path. Example: exampledir/exampleobject.txt. */
const char *object_name = "exampledir/exampleobject.txt";
/* Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou. */
const char *region = "yourRegion";
void init_options(oss_request_options_t *options)
{
options->config = oss_config_create(options->pool);
/* Use a char* string to initialize data of the aos_string_t type. */
aos_str_set(&options->config->endpoint, endpoint);
/* 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. */
aos_str_set(&options->config->access_key_id, getenv("OSS_ACCESS_KEY_ID"));
aos_str_set(&options->config->access_key_secret, getenv("OSS_ACCESS_KEY_SECRET"));
// Specify two additional parameters.
aos_str_set(&options->config->region, region);
options->config->signature_version = 4;
/* Specify whether to use CNAME. The value 0 indicates that CNAME is not used. */
options->config->is_cname = 0;
/* Specify network parameters, such as the timeout period. */
options->ctl = aos_http_controller_create(options->pool, 0);
}
int main(int argc, char *argv[])
{
/* Call the aos_http_io_initialize method in main() to initialize global resources, such as network resources and memory resources. */
if (aos_http_io_initialize(NULL, 0) != AOSE_OK) {
exit(1);
}
/* Create a memory pool to manage memory. aos_pool_t is equivalent to apr_pool_t. The code used to create a memory pool is included in the APR library. */
aos_pool_t *pool;
/* Create a memory pool. The value of the second parameter is NULL. This value indicates that the pool does not inherit other memory pools. */
aos_pool_create(&pool, NULL);
/* Create and initialize options. This parameter includes global configuration information, such as endpoint, access_key_id, access_key_secret, is_cname, and curl. */
oss_request_options_t *oss_client_options;
/* Allocate the memory resources in the memory pool to the options. */
oss_client_options = oss_request_options_create(pool);
/* Initialize oss_client_options. */
init_options(oss_client_options);
/* Initialize the parameters. */
aos_string_t bucket;
aos_string_t object;
aos_string_t file;
aos_table_t *headers = NULL;
aos_table_t *params = NULL;
aos_table_t *resp_headers = NULL;
aos_status_t *resp_status = NULL;
aos_str_set(&bucket, bucket_name);
aos_str_set(&object, object_name);
/* Resize the image to 100 × 100 pixels. */
params = aos_table_make(pool, 1);
apr_table_set(params, OSS_PROCESS, "image/resize,m_fixed,w_100,h_100");
/* Save the processed image to your local computer. */
aos_str_set(&file, "yourLocalFileName");
resp_status = oss_get_object_to_file(oss_client_options, &bucket, &object, headers, params, &file, &resp_headers);
if (aos_status_is_ok(resp_status)) {
printf("get object to file succeeded\n");
} else {
printf("get object to file failed\n");
}
/* Release the memory pool. This operation releases the memory resources allocated for the request. */
aos_pool_destroy(pool);
/* Release the allocated global resources. */
aos_http_io_deinitialize();
return 0;
}複数のIMGパラメーターを使用して画像を処理し、ローカルコンピューターに保存します
次のコードでは、複数のIMGパラメーターを使用してイメージを処理する方法の例を示します。 パラメーターはスラッシュ (/) で区切ります。
#include "oss_api.h"
#include "aos_http_io.h"
/* 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. */
const char *endpoint = "yourEndpoint";
/* Specify the name of the bucket. Example: examplebucket. */
const char *bucket_name = "examplebucket";
/* Specify the full path of the object. Do not include the bucket name in the full path. Example: exampledir/exampleobject.txt. */
const char *object_name = "exampledir/exampleobject.txt";
/* Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou. */
const char *region = "yourRegion";
void init_options(oss_request_options_t *options)
{
options->config = oss_config_create(options->pool);
/* Use a char* string to initialize data of the aos_string_t type. */
aos_str_set(&options->config->endpoint, endpoint);
/* 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. */
aos_str_set(&options->config->access_key_id, getenv("OSS_ACCESS_KEY_ID"));
aos_str_set(&options->config->access_key_secret, getenv("OSS_ACCESS_KEY_SECRET"));
// Specify two additional parameters.
aos_str_set(&options->config->region, region);
options->config->signature_version = 4;
/* Specify whether to use CNAME. The value 0 indicates that CNAME is not used. */
options->config->is_cname = 0;
/* Specify network parameters, such as the timeout period. */
options->ctl = aos_http_controller_create(options->pool, 0);
}
int main(int argc, char *argv[])
{
/* Call the aos_http_io_initialize method in main() to initialize global resources, such as network resources and memory resources. */
if (aos_http_io_initialize(NULL, 0) != AOSE_OK) {
exit(1);
}
/* Create a memory pool to manage memory. aos_pool_t is equivalent to apr_pool_t. The code used to create a memory pool is included in the APR library. */
aos_pool_t *pool;
/* Create a memory pool. The value of the second parameter is NULL. This value indicates that the pool does not inherit other memory pools. */
aos_pool_create(&pool, NULL);
/* Create and initialize options. This parameter includes global configuration information, such as endpoint, access_key_id, access_key_secret, is_cname, and curl. */
oss_request_options_t *oss_client_options;
/* Allocate the memory resources in the memory pool to the options. */
oss_client_options = oss_request_options_create(pool);
/* Initialize oss_client_options. */
init_options(oss_client_options);
/* Initialize the parameters. */
aos_string_t bucket;
aos_string_t object;
aos_string_t file;
aos_table_t *headers = NULL;
aos_table_t *params = NULL;
aos_table_t *resp_headers = NULL;
aos_status_t *resp_status = NULL;
aos_str_set(&bucket, bucket_name);
aos_str_set(&object, object_name);
/* Resize the image to 100 × 100 pixels and rotate the image 90 degrees. */
params = aos_table_make(pool, 1);
apr_table_set(params, OSS_PROCESS, "image/resize,m_fixed,w_100,h_100/rotate,90");
/* Save the processed image to your local computer. */
aos_str_set(&file, "yourLocalFileName");
resp_status = oss_get_object_to_file(oss_client_options, &bucket, &object, headers, params, &file, &resp_headers);
if (aos_status_is_ok(resp_status)) {
printf("get object to file succeeded\n");
} else {
printf("get object to file failed\n");
}
/* Release the memory pool. This operation releases the memory resources allocated for the request. */
aos_pool_destroy(pool);
/* Release the allocated global resources. */
aos_http_io_deinitialize();
return 0;
}画像スタイルを使用して画像を処理する
イメージスタイルを作成します。
複数のIMGパラメータをイメージスタイルに追加して、バケットに保存されているイメージに対して複雑な操作を実行できます。 詳細については、「イメージスタイル」をご参照ください。
イメージスタイルを使用してイメージを処理します。
#include "oss_api.h" #include "aos_http_io.h" /* 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. */ const char *endpoint = "yourEndpoint"; /* Specify the name of the bucket. Example: examplebucket. */ const char *bucket_name = "examplebucket"; /* Specify the full path of the object. Do not include the bucket name in the full path. Example: exampledir/exampleobject.txt. */ const char *object_name = "exampledir/exampleobject.txt"; /* Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou. */ const char *region = "yourRegion"; void init_options(oss_request_options_t *options) { options->config = oss_config_create(options->pool); /* Use a char* string to initialize data of the aos_string_t type. */ aos_str_set(&options->config->endpoint, endpoint); /* 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. */ aos_str_set(&options->config->access_key_id, getenv("OSS_ACCESS_KEY_ID")); aos_str_set(&options->config->access_key_secret, getenv("OSS_ACCESS_KEY_SECRET")); // Specify two additional parameters. aos_str_set(&options->config->region, region); options->config->signature_version = 4; /* Specify whether to use CNAME. The value 0 indicates that CNAME is not used. */ options->config->is_cname = 0; /* Specify network parameters, such as the timeout period. */ options->ctl = aos_http_controller_create(options->pool, 0); } int main(int argc, char *argv[]) { /* Call the aos_http_io_initialize method in main() to initialize global resources, such as network resources and memory resources. */ if (aos_http_io_initialize(NULL, 0) != AOSE_OK) { exit(1); } /* Create a memory pool to manage memory. aos_pool_t is equivalent to apr_pool_t. The code used to create a memory pool is included in the APR library. */ aos_pool_t *pool; /* Create a memory pool. The value of the second parameter is NULL. This value indicates that the pool does not inherit other memory pools. */ aos_pool_create(&pool, NULL); /* Create and initialize options. This parameter includes global configuration information, such as endpoint, access_key_id, access_key_secret, is_cname, and curl. */ oss_request_options_t *oss_client_options; /* Allocate the memory resources in the memory pool to the options. */ oss_client_options = oss_request_options_create(pool); /* Initialize oss_client_options. */ init_options(oss_client_options); /* Initialize the parameters. */ aos_string_t bucket; aos_string_t object; aos_string_t file; aos_table_t *headers = NULL; aos_table_t *params = NULL; aos_table_t *resp_headers = NULL; aos_status_t *resp_status = NULL; aos_str_set(&bucket, bucket_name); aos_str_set(&object, object_name); /* Specify the image style. */ params = aos_table_make(pool, 1); /* Set yourCustomStyleName to the name of the image style that you created in Step 1. */ apr_table_set(params, OSS_PROCESS, "style/yourCustomStyleName"); /* Save the processed image to your local computer. */ aos_str_set(&file, "yourLocalFileName"); resp_status = oss_get_object_to_file(oss_client_options, &bucket, &object, headers, params, &file, &resp_headers); if (aos_status_is_ok(resp_status)) { printf("get object to file succeeded\n"); } else { printf("get object to file failed\n"); } /* Release the memory pool. This operation releases the memory resources allocated for the request. */ aos_pool_destroy(pool); /* Release the allocated global resources. */ aos_http_io_deinitialize(); return 0; }
IMGパラメータを含む署名付きオブジェクトURLを生成する
プライベートオブジェクトのURLに署名する必要があります。 署名付きURLにIMGパラメーターを追加することはできません。 プライベートオブジェクトを処理する場合は、署名にIMGパラメーターを追加します。
#include "oss_api.h"
#include "aos_http_io.h"
/* 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. */
const char *endpoint = "yourEndpoint";
/* Specify the name of the bucket. Example: examplebucket. */
const char *bucket_name = "examplebucket";
/* Specify the full path of the object. Do not include the bucket name in the full path. Example: exampledir/exampleobject.txt. */
const char *object_name = "exampledir/exampleobject.txt";
/* Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou. */
const char *region = "yourRegion";
void init_options(oss_request_options_t *options)
{
options->config = oss_config_create(options->pool);
/* Use a char* string to initialize data of the aos_string_t type. */
aos_str_set(&options->config->endpoint, endpoint);
/* 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. */
aos_str_set(&options->config->access_key_id, getenv("OSS_ACCESS_KEY_ID"));
aos_str_set(&options->config->access_key_secret, getenv("OSS_ACCESS_KEY_SECRET"));
// Specify two additional parameters.
aos_str_set(&options->config->region, region);
options->config->signature_version = 4;
/* Specify whether to use CNAME. The value 0 indicates that CNAME is not used. */
options->config->is_cname = 0;
/* Configure network parameters, such as the timeout period. */
options->ctl = aos_http_controller_create(options->pool, 0);
}
int main(int argc, char *argv[])
{
/* Call the aos_http_io_initialize method in main() to initialize global resources, such as network resources and memory resources. */
if (aos_http_io_initialize(NULL, 0) != AOSE_OK) {
exit(1);
}
/* Create a memory pool to manage memory. aos_pool_t is equivalent to apr_pool_t. The code used to create a memory pool is included in the APR library. */
aos_pool_t *pool;
/* Create a memory pool. The value of the second parameter is NULL. This value indicates that the pool does not inherit other memory pools. */
aos_pool_create(&pool, NULL);
/* Create and initialize options. This parameter includes global configuration information, such as endpoint, access_key_id, access_key_secret, is_cname, and curl. */
oss_request_options_t *oss_client_options;
/* Allocate the memory resources in the memory pool to the options. */
oss_client_options = oss_request_options_create(pool);
/* Initialize oss_client_options. */
init_options(oss_client_options);
/* Initialize the parameters. */
aos_string_t bucket;
aos_string_t object;
aos_table_t *params = NULL;
aos_http_request_t *req;
char *url_str;
apr_time_t now;
int64_t expire_time;
aos_str_set(&bucket, bucket_name);
aos_str_set(&object, object_name);
/* Resize the image to 100 × 100 pixels. */
params = aos_table_make(pool, 1);
apr_table_set(params, OSS_PROCESS, "image/resize,m_fixed,w_100,h_100");
req = aos_http_request_create(pool);
req->method = HTTP_GET;
req->query_params = params;
/* Specify the validity period (expire_time) in seconds. */
now = apr_time_now();
expire_time = now / 1000000 + 10 * 60;
/* Generate a signed URL. */
url_str = oss_gen_signed_url(oss_client_options, &bucket, &object, expire_time, req);
printf("url: %s\n", url_str);
/* Release the memory pool. This operation releases memory resources allocated for the request. */
aos_pool_destroy(pool);
/* Release the allocated global resources. */
aos_http_io_deinitialize();
return 0;
}