PR #23435 opened by toots
URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23435
Patch URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23435.patch

Add `.props` to `AV_CODEC_ID_APPLE_APAC`.

The biggest question is: should this codec have `AV_CODEC_PROP_INTRA_ONLY`?

I seems like it shouldn't. The codec has a notion of "Audio Synchronization 
Packet" who, although only described in the context of a HLS stream, seem to 
indicate that they are required to decode the following packets:
> APAC encoded content can be segmented for HLS streaming. Each segment
must commence with an Audio Synchronization Frame (ASP) packet, which is an
independently decodable packet. It is recommended to configure the encoder to
utilize a regular ASP interval of 1.6s duration which results in a value of 75 
for a
sampling rate of 48 kHz. When constructing an HLS stream based on APAC
content, certain information about the content may be required to adequately
describe an APAC track in an HLS playlist. This information may include the 
Profile
and Level of the content, as well as the channel layout tag. The HLS Authoring
Specification provides more details. 

Source: 
https://developer.apple.com/av-foundation/Apple-Positional-Audio-Codec.pdf


>From 1ffc2abd1415b66f6d7d9a4f6e1e18177d186df9 Mon Sep 17 00:00:00 2001
From: Romain Beauxis <[email protected]>
Date: Wed, 10 Jun 2026 08:27:26 -0500
Subject: [PATCH] avcodec/codec_id: add .props to AV_CODEC_ID_APPLE_APAC

Signed-off-by: Romain Beauxis <[email protected]>
---
 libavcodec/codec_desc.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/libavcodec/codec_desc.c b/libavcodec/codec_desc.c
index 011cf4a0f9..7a16d002b9 100644
--- a/libavcodec/codec_desc.c
+++ b/libavcodec/codec_desc.c
@@ -3580,6 +3580,7 @@ static const AVCodecDescriptor codec_descriptors[] = {
         .type      = AVMEDIA_TYPE_AUDIO,
         .name      = "apple_apac",
         .long_name = NULL_IF_CONFIG_SMALL("Apple Positional Audio Codec"),
+        .props     = AV_CODEC_PROP_LOSSY,
     },
 
     /* subtitle codecs */
-- 
2.52.0

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