[FFmpeg-devel] [PATCH] Clearer wording of audio channel maping limitations

[Tim Nicholson]

Clément Bœsch wrote:-

> 
> On Wed, Dec 21, 2011 at 04:18:53PM +0000, Tim Nicholson wrote:
> [...]
> 
>>  Should I keep them as separate patch stages, or should I have merged them?
>> 
>>  I tried a rebase but nothing happened....
>> 
> 
> You need to edit your patch and submit it again. The simpler thing to do
> in your case is to do some changes and then commit them with `git commit
> -a --amend`. It should squash your changes within the last commit.
> 

Oh. so much to learn, and so little time to do it....

Thanks for bearing with me....

I have included the squashed version should anyone else care to comment...

-- 

Tim

From 5b2af49325fc21163054acc4d3be1270a90ddc12 Mon Sep 17 00:00:00 2001
From: Tim Nicholson <Tim.Nicholson at bbc.co.uk>
Date: Wed, 21 Dec 2011 17:12:05 +0000
Subject: [PATCH] Clearer explanation of audio channel mapping restrictions

---
 doc/ffmpeg.texi |   10 +++++++---
 1 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/doc/ffmpeg.texi b/doc/ffmpeg.texi
index 553d759..83a45a8 100644
--- a/doc/ffmpeg.texi
+++ b/doc/ffmpeg.texi
@@ -825,9 +825,13 @@ The following example split the channels of a stereo input into streams:
 ffmpeg -i stereo.wav -map 0:0 -map 0:0 -map_channel 0.0.0:0.0 -map_channel 0.0.1:0.1 -y out.ogg
 @end example
 
-Note that "-map_channel" is currently limited to the scope of one input for
-each output; you can't for example use it to pick multiple input audio files
-and mix them into one single output.
+Note that currently each output stream can only contain channels from a single
+input stream; you can't for example use "-map_channel" to pick multiple input
+audio channels contained in different streams (from the same or different files)
+and merge them into a single output stream. It is therefore not currently
+possible, for example, to turn two separate mono streams into a single stereo
+stream. However spliting a stereo stream into two single channel mono streams
+is possible.
 
 @item -map_metadata[:@var{metadata_type}][:@var{index}] @var{infile}[:@var{metadata_type}][:@var{index}] (@emph{output,per-metadata})
 Set metadata information of the next output file from @var{infile}. Note that
-- 
1.7.7