extractor: youtube: Set extension of AAC audio formats to m4a.

This, in particular, eases downloading both audio and videos in DASH formats
before muxing them, which alleviates the problem that I exposed on issue

Furthermore, one may argue that this is, indeed, the case for correctness's
sake.

Signed-off-by: Rogério Brito <rbrito@ime.usp.br>

diff --git a/youtube_dl/extractor/youtube.py b/youtube_dl/extractor/youtube.py
index fb7c42830781bf4cbf3f3ba78547e6defe5b13c5..cfc142f2658944de57aaa48821d9480f596fd61b 100644 (file)
--- a/youtube_dl/extractor/youtube.py
+++ b/youtube_dl/extractor/youtube.py
@@ -237,9 +237,9 @@ class YoutubeIE(YoutubeBaseInfoExtractor, SubtitlesInfoExtractor):
         '137': 'mp4',
         '138': 'mp4',
         '139': 'mp4',
-        '140': 'mp4',
-        '141': 'mp4',
-        '160': 'mp4',
+        '140': 'm4a',
+        '141': 'm4a',
+        '160': 'm4a',
 
         # Dash webm
         '171': 'webm',