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ROSBridge : How are data arrays represented and sent via JSON?

asked 2013-12-23 08:23:11 -0600

trianta2
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updated 2014-01-28 17:07:22 -0600

ngrennan
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If I send a uint8[] array with 1 byte of data (of value 0x00) over ROSBridge, I receive the string "AA==" on the client end.

How does ROSbridge handle the conversion of byte arrays to strings? How can I retrieve my original data of 0x00?

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I don't know how exactly rosbridge handles the data, but since the websockets are used, the memory spaces of payload and trailer are allocated. With websockets data is sent in between 0x00 and 0xFF in a packet. You can examine the rosbridge_library codes to see the conversion.

mozcelikors ( 2013-12-23 10:58:25 -0600 )edit

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answered 2013-12-23 12:17:08 -0600

trianta2
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Apparently it's common for people to encode raw binary to Base64 before transmitting data via JSON objects. That's what was happening. I was able to decode the message from Base64 and retrieve my data.

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Asked: 2013-12-23 08:23:11 -0600

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