libavcodec - the option name "ac" is duplicated

[cnt]

What I do:
I am trying to list AVOptions of libavcodec in a GUI interface.
I need to have a unique key for each AVOption. I thought it was possible with the name of the option...

My problem:
There are two options with the same name "ac". This option could be the number of audio channels, or the arithmetic coder.

Content of libavcodec/options_tables.h:

...
{"ac", "set number of audio channels", OFFSET(channels), AV_OPT_TYPE_INT, {.i64 = DEFAULT }, INT_MIN, INT_MAX, A|D|E},
...
{"ac", "arithmetic coder", 0, AV_OPT_TYPE_CONST, {.i64 = FF_CODER_TYPE_AC }, INT_MIN, INT_MAX, V|E, "coder"},
...

[Carl Eugen Hoyos]

I don't think there are two options with the name ac.
There is one option -ac with sets the number of audio channels, for example -ac 2 and there is an option -coder that allows to select Huffman or arithmetic coder, for example with -coder ac. How can these options be confused?

[cnt]

The command line is fine.

But to list AVOptions on my GUI application, I use av_opt_next function. This function returns two options with the same name : "ac".
If I look at the file libavcodec/options_tables.h, I see two AVOptions which correpond to "ac":

• one with the help : "set number of audio channels".
• the other one with the help : "arithmetic coder".

[Michael Niedermayer]

Theres one option and one constant.
If you want to make a list of options that can be set to somevalue or another then your gui would skip constants (AV_OPT_TYPE_CONST). These are not options the user could set to something

If you want to make a list of value that a single option can be set to then you would only consider all AV_OPT_TYPE_CONST which had a matching unit to the specific option