Regression in compressed_depth_image_transport with old bagfiles (Unsupported image format: 16UC1; compressedDepth)

[tlind]

I'm experiencing problems with existing rosbags, when trying to republish compressed depth image messages. The regression is caused by commit a710d4a in 1.14.0 (ROS Noetic) which introduced the new RVL depth compression.

The error message is:

Unsupported image format: "16UC1; compressedDepth"

and occurs in:

compressed_depth_image_transport::decodeCompressedDepthImage()

The check for the old format introduced in that commit is not able to match the above format string:

image_transport_plugins/compressed_depth_image_transport/src/codec.cpp

Lines 72 to 89 in 73824bc

	// Assign image encoding
	const size_t split_pos = message.format.find(';');
	const std::string image_encoding = message.format.substr(0, split_pos);
	std::string compression_format;
	// Older version of compressed_depth_image_transport supports only png.
	if (split_pos == std::string::npos) {
	compression_format = "png";
	} else {
	std::string format = message.format.substr(split_pos);
	if (format.find("compressedDepth png") != std::string::npos) {
	compression_format = "png";
	} else if (format.find("compressedDepth rvl") != std::string::npos) {
	compression_format = "rvl";
	} else {
	ROS_ERROR("Unsupported image format: %s", message.format.c_str());
	return sensor_msgs::Image::Ptr();
	}
	}

This bug might have been introduced due to the badly maintained documentation of the format field (#56).

[tlind]

I have added a tiny pull request (#64) that should address this issue.

[matemat13]

Just hit this bug today when replaying some old rosbag. Can we pls merge the related PR? In any case - thanks a lot for the fix :)

[Sanic]

Thanks for the fix @tlind ! We also had the same problem.

@mjcarroll I was just wondering if there is already a deb package build scheduled for a new version (v1.x) which contains this fix?