From: Michael Koch <astroelectronic@t-online.de>
To: ffmpeg-devel@ffmpeg.org
Subject: Re: [FFmpeg-devel] [PATCH 2/2] doc/utils/eval: clarify meaning of random* seed value
Date: Wed, 3 Jan 2024 18:04:33 +0100
Message-ID: <0ba345a6-f5e9-0ac9-4f86-af85596ea08e@t-online.de> (raw)
In-Reply-To: <ZZWH5w8BVTYSQ5qC@mariano>
On one hand, it's good that the 10 variables for ld() and st() are
initialized with zero.
But on the other hand, zero is obviously the worst possible seed value
for the random generator.
For example, make a 1000x1000 image with red color, and then fill one
pixel at a random position with yellow color. Surprise surprise, the
pixel is in the top left corner. That's not what a user expects from a
random generator. It took me some time to figure out what's the problem,
and how to set a better seed value.
Michael
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next prev parent reply other threads:[~2024-01-03 17:04 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-01-01 19:38 [FFmpeg-devel] [PATCH 1/2] libavutil/eval: introduce UINT64_MAX constant Stefano Sabatini
2024-01-01 19:38 ` [FFmpeg-devel] [PATCH 2/2] doc/utils/eval: clarify meaning of random* seed value Stefano Sabatini
2024-01-03 11:20 ` Michael Koch
2024-01-03 16:14 ` Stefano Sabatini
2024-01-03 17:04 ` Michael Koch [this message]
2024-01-03 18:36 ` Michael Koch
2024-01-03 22:29 ` Michael Niedermayer
2024-01-02 0:10 ` [FFmpeg-devel] [PATCH 1/2] libavutil/eval: introduce UINT64_MAX constant Michael Niedermayer
2024-01-03 16:17 ` Stefano Sabatini
2024-01-03 19:40 ` Michael Niedermayer
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