IPP 7.0.5 H264 init tables thread safe

[selea]

I think that the variable

Ipp32u H264VideoDecoder::m_iInstances = 0;

it's not threadsafe. So could be a problem if multiple threads access the variable, andH264Bitstream::ReleaseTables could be released more than one time.

Moreover the variable

bool H264Bitstream::m_bTablesInited = false;

it's not threadsafe so you can Init or destroy the H264Table more that once.

Do you think it's better to use a vm_mutex to make the initializzation threadsafe?

[Pavel_V_Intel]

Good day.

I will probably add mutex in future.