OverflowError when adding stream with float framerate

[caspervdw]

When adding a stream with a floating point framerate, as follows:

    import av

output = av.open('test.avi', 'w')
output.add_stream('rawvideo', rate=30.000001)

I receive the following error message: --------------------------------------------------------------------------- OverflowError Traceback (most recent call last) in () 4 5 output = av.open('test.avi', 'w', format=None, options=dict()) ----> 6 output.add_stream('rawvideo', rate=30.)

av/container/output.pyx in av.container.output.OutputContainer.add_stream (src\av\container\output.c:2656)()

av/container/output.pyx in av.container.output.OutputContainer.add_stream (src\av\container\output.c:2322)()

OverflowError: Python int too large to convert to C long

My av version is 0.3.3, on Win64, Python 3.5.2. My guess is that it gets converted to a fraction, which contains an integer that is too large for a Clong. Is there a possibility to get around this?

[vbkaisetsu]

30.000001 is interpreted as 30.000001000000001 in Fraction. This error does not occur when the argument is passed as a string.

>>> from fractions import Fraction
>>> Fraction(30.000001)
Fraction(8444249582794657, 281474976710656)
>>> Fraction('30.000001')
Fraction(30000001, 1000000)

output.add_stream('rawvideo', rate='30.000001')

[caspervdw]

@vbkaisetsu thanks, the following solved this for me. I limit the rate to 4 decimals, as I noted that MPEG-4 only allows a timebase of max 66535.

import av

output = av.open('test.avi', 'w')
output.add_stream('rawvideo', rate='{0:.4f}'.format(30.000001))

[vbkaisetsu]

In that case, I think you can also use limit_denominator:

stream = output.add_stream(codec, rate=Fraction(export_rate).limit_denominator(65535))

[caspervdw]

Ok thanks, that works too indeed

[mikeboers]

Does anyone know if there is a way to detect what the maximum denominator is for a codec except for hard-coding one?

We could bypass the overflow error by limiting to 2**32-1, or (I'm leaning towards) throwing an error of our own that is more descriptive.

[github-actions[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[jlaine]

Let's keep this alive.

[github-actions[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.