Can't see logs of x264 lib

Question

I have a C++ solution which uses x264.lib. I've set params.i_log_level = X264_LOG_DEBUG; in order to be able to see some logging from x264 lib. However during debugging in Visual Studio Output window I do not see any x264 related logs.

How can I see those logs?

Answer 1

Enabling log level, you leave default logging handler to generate debug output. This writes to stderr and the output does not appear on Visual Studio output window.

static void x264_log_default( void *p_unused, int i_level, const char *psz_fmt, 
  va_list arg )
{
    // ...
    fprintf( stderr, "x264 [%s]: ", psz_prefix );
    vfprintf( stderr, psz_fmt, arg );

You need to provide your own log function in params.pf_log and have the data passed to OutputDebugString API. This way it is going to come up on VS output window.