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Torch Object Storage

Basic concepts

Saving processed files

TOS does not save processed images or video frames by default. However, you can add persistence parameters to the processing URL to save these files to a designated bucket. This topic outlines the relevant parameters for saving processed images and video frames and provides examples of how to use them.

Notes

To save a processed image or video frame, your account must have read permissions for the bucket that contains the original image or video, and write permissions for the bucket that will store the processed image or video frame.

Anonymous users must specify a bucket with public write access for saving processed images and video frames.

The source and target buckets must be in the same region.

The default access permission for processed images and video frames is "Private", and the default storage type is "Standard Storage".

By default, processed images and video frames use the server-side encryption method of the bucket to which they are saved. If the target bucket uses SSE-KMS, ensure your account has permission for the bucket's Key Management Service (KMS) key.

Supported parameters

Parameter	Description	Value	Required
x-tos-save-object	Specifies the name of the processed image or video frame in the target bucket. The name must be encoded in URL-safe Base64.	A Base64-encoded string.	Yes
x-tos-save-bucket	Specifies the name of the bucket for saving the processed image or video frame. The name must be encoded in URL-safe Base64.	A Base64-encoded string. The processed image or video frame will be saved to the same bucket as the original image or video if you do not specify a bucket.	No

Examples

There are two methods you can use to save a processed image.

Generate a presigned URL that includes image processing and persistence parameters, and use it to save the processed image.

Add persistence parameters to the URL for accessing and processing the image, and then save the processed image to the specified bucket. Note that this method uses anonymous access and requires the target bucket to have public write access. Otherwise, the save operation will fail.

warning

The URLs below demonstrate how to add persistence parameters. However, since you do not have write permissions for the example bucket, accessing these URLs will result in an Access Denied message.

Saving a resized image

Processed image URL: https://tos-tools.tos-cn-beijing.volces.com/misc/sample.png?x-tos-process=image/resize,w_100

Save the processed image as "abc.png" in the same bucket as the original image:

https://tos-tools.tos-cn-beijing.volces.com/misc/sample.png?x-tos-process=image/resize,w_100&x-tos-save-object=YWJjLnBuZw==

Save the processed image as "abc.png" in a bucket named "arctic":

https://tos-tools.tos-cn-beijing.volces.com/misc/sample.png?x-tos-process=image/resize,w_100&x-tos-save-object=YWJjLnBuZw==&x-tos-save-bucket=YXJjdGlj

Saving a video frame

Video frame URL: https://tos-tools.tos-cn-beijing.volces.com/misc%2Fvideo.mp4?x-tos-process=video/snapshot,t_26000,w_400,h_200,f_jpg

Save the video frame as "abc.jpg" in the same bucket as the original image:

https://tos-tools.tos-cn-beijing.volces.com/misc%2Fvideo.mp4?x-tos-process=video/snapshot,t_26000,w_400,h_200,f_jpg&x-tos-save-object=YWJjLnBuZw==

Save the video frame as "abc.jpg" in a bucket named "arctic":

https://tos-tools.tos-cn-beijing.volces.com/misc%2Fvideo.mp4?x-tos-process=video/snapshot,t_26000,w_400,h_200,f_jpg&x-tos-save-object=YWJjLnBuZw==&x-tos-save-bucket=YXJjdGlj

Last updated: 2026.10.13 10:20:02