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SJTU-ViSYS / M2DGR

M2DGR： a Multi-modal and Multi-scenario Dataset for Ground Robots(RA-L2021 & ICRA2022)
MIT License
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Why is the Image Topic in a Compressed Form？ #85

Closed kenan9875645 closed 1 year ago

kenan9875645 commented 1 year ago

"/camera/aligned_depth_to_color/image_raw/compressed /camera/color/image_raw/compressed /camera/fifth/image_raw/compressed /camera/fourth/image_raw/compressed"

Above is the ros topic of room_01.bag file output. How can I obtain the topic of /camera/color/image_raw/ from /camera/color/image_raw/compressed?

DreamWaterFound commented 1 year ago

Using compressed images can greatly reduce unnecessary bandwidth consumption and storage space usage. You can calculate how much bandwidth would be consumed if you were to directly publish and save the raw images, considering the number of image data channels.

If you need to fetch the original images, I recommend using the image_transport plugin. You can find specific methods and instructions here. You can directly write code in your program to call the image_transport API, or you can use image_transport's command-line tools to republish the compressed images as original images.