Re-order options for testsrc family of filters in manual

[Misaki]

According to the manual, option four for filter 'color' should be sample aspect ratio: https://ffmpeg.org/ffmpeg-filters.html

However, the command ffmpeg -filter_complex "color=white:160x160:1:1:10" output.mp4 produces output of 1 frame.

[Carl Eugen Hoyos]

Replying to Misaki:

According to the manual, option four for filter 'color' should be sample aspect ratio: https://ffmpeg.org/ffmpeg-filters.html

Where is this specified?

[llogan]

Don't rely on shorthand: it can be ambiguous or confusing and lead to mistakes, and there may be no guarantee that the order will always remain the same. Include the option names with your values: color=c=white:s=160x160:r=1:d=10:sar=1.

The manual entry is an unorganized combination for the color and other related testsrc based source filters, so trying to count the position of each supported option (and excluding the options specific to the other filters) is not recommended. If you must use shortcuts then refer to ffmpeg -h filter=color instead. As you can see from this output sar is currently option five.

To address this the order in the manual can be changed to: level, c, s, r, d, sar, alpha, n. I did not check the order of other non-testsrc filters. To check them all is arguably a "wontfix" ticket out of pure laziness because reviewing each filter is going to be a boring, mindless job as there are at least 350 filters I estimate, and filter authors may not sync the option order in future filters. Patch welcome!

Your output is one frame because you told it to make a frame rate of 1 and a duration of 1 second.

[llogan]

Fixed in 555119bd762540a9f17a61bdd92329c8b8feb1e0.