panic: runtime error: slice bounds out of range

[yjgs]

I downloaded the program to run in ios12. The following error occurred when scanning the dynamic QR code. How to solve it? panic: runtime error: slice bounds out of range

The error occurred in this line: try decoder?.decodeChunk(str)

[liwenkui]

the txqr.framework project using is not LT-code implementation.i switch to the LT-code implementation,sometimes it's working but sometimes facing with memory crash problem.