audio: introduce a new type to hold audio frames

This is pretty pointless, but I believe it allows us to claim that the
new code is not affected by the copyright of the old code. This is
needed, because the original mp_audio struct was written by someone who
has disagreed with LGPL relicensing (it was called af_data at the time,
and was defined in af.h).

The "GPL'ed" struct contents that surive are pretty trivial: just the
data pointer, and some metadata like the format, samplerate, etc. - but
at least in this case, any new code would be extremely similar anyway,
and I'm not really sure whether it's OK to claim different copyright. So
what we do is we just use AVFrame (which of course is LGPL with 100%
certainty), and add some accessors around it to adapt it to mpv
conventions.

Also, this gets rid of some annoying conventions of mp_audio, like the
struct fields that require using an accessor to write to them anyway.

For the most part, this change is only dumb replacements of mp_audio
related functions and fields. One minor actual change is that you can't
allocate the new type on the stack anymore.

Some code still uses mp_audio. All audio filter code will be deleted, so
it makes no sense to convert this code. (Audio filters which are LGPL
and which we keep will have to be ported to a new filter infrastructure
anyway.) player/audio.c uses it because it interacts with the old filter
code. push.c has some complex use of mp_audio and mp_audio_buffer, but
this and pull.c will most likely be rewritten to do something else.

1 files changed, 5 insertions, 5 deletions

diff --git a/player/core.h b/player/core.h
index bdb8b4c3a5..ea7e0c1ec1 100644
--- a/player/core.h
+++ b/player/core.h
@@ -28,7 +28,7 @@
 #include "common/common.h"
 #include "options/options.h"
 #include "sub/osd.h"
-#include "audio/audio.h"
+#include "audio/aframe.h"
 #include "video/mp_image.h"
 #include "video/out/vo.h"
 
@@ -205,10 +205,10 @@ struct ao_chain {
     double ao_resume_time;
 
     // 1-element input frame queue.
-    struct mp_audio *input_frame;
+    struct mp_aframe *input_frame;
 
-    // Last known input_mpi format (so vf can be reinitialized any time).
-    struct mp_audio input_format;
+    // Last known input_mpi format (so af can be reinitialized any time).
+    struct mp_aframe *input_format;
 
     struct track *track;
     struct lavfi_pad *filter_src;
@@ -313,7 +313,7 @@ typedef struct MPContext {
     struct lavfi *lavfi;
 
     struct ao *ao;
-    struct mp_audio *ao_decoder_fmt; // for weak gapless audio check
+    struct mp_aframe *ao_decoder_fmt; // for weak gapless audio check
     struct ao_chain *ao_chain;
 
     struct vo_chain *vo_chain;