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• Why does Apple support H.265 playback, but not when using HLS ? [closed]

  13 mars, par clark wu

  Apple devices (iPhone, iPad, macOS Safari) can natively play H.265 (HEVC) videos in .mp4 or .mov format. However, when I try to convert the same video to HLS, it fails to play. Here’s what I tested :

  


  Test Cases

  


  ✅ Directly playing H.265 .mp4 → Works fine

  


  ❌ H.265 + Opus → HLS (fMP4) → Fails

  


  ❌ H.265 + AAC → HLS (TS) → Fails

  


  ✅ H.264 + Opus → HLS fMP4 → Works fine (video + audio)

  


  ✅ H.264 + Opus → HLS TS → Video plays, but no audio

  


  ❌ H.265 + AAC → HLS fMP4 → Doesn’t play at all

  


  FFmpeg Commands Used

  


  1️⃣ H.265 + Opus (fMP4 segments)

  


  ffmpeg -i input.mp4 -c:v copy -c:a copy -hls_segment_type fmp4 -hls_time 10 -hls_list_size 0 -hls_flags independent_segments output.m3u8


  


  2️⃣ H.265 + AAC (TS segments)

  


  ffmpeg -i input.mp4 -c:v copy -c:a copy -hls_time 10 -hls_list_size 0 -hls_flags independent_segments output.m3u8


  


  Playback Attempts

  


  Vidstack.js player (Fails)

  


  Several online M3U8 players (All fail)

  


  Key Questions

  


  Why does Apple support H.265 in MP4 but not in HLS ?

  


  Is this an HLS specification limitation ?

  


  Does the audio codec (Opus / AAC) affect playback ?

  


  Does HLS require a specific HEVC profile/level ?

  


  Is HLS only compatible with AVC, not HEVC ?

  


  Looking for Answers

  


  Has anyone successfully played H.265 + HLS on Apple devices ?

  


  Are there any official Apple HLS specifications regarding HEVC support ?

  


  Possible workarounds or alternative solutions ?

  


  Would appreciate any insights or help from the community ! Thanks !

  


• Official RealVideo Specifications

  29 juillet 2010, par Multimedia Mike — General

  A little birdie tipped me off to a publicly-accessible URL on the Helix community site (does anyone actually use Helix ?) that contains a bunch of specifications for RealVideo 8 and 9. I have been sifting through the documents to see exactly what they contain as the different files seem to be higher revisions of the same documents. Here is the title, date, and version of each PDF document :

  • RNDecoderPerformanceARM.pdf : Decoder Performance on StrongARM and XScale ; May 12, 2003 ; Version 1.1
  • rv89_decoder_summary.pdf : RealVideo 8/9 Combo Decoder Summary ; October 23, 2002 ; Version 1.0
  • rv9_dec_external_spec_v14.pdf : RealVideo 9 External Specification ; November 7, 2003 ; Version 1.4
  • rv8_dec_external_spec_v20.pdf : RealVideo 8 External Specification ; September 19, 2002 ; Version 2.0
  • RV8DecoderExternalSpecificationv201.pdf : RealVideo 8 External Specification ; October 20, 2006 ; Version 2.01
  • RV8DecoderExternalSpecificationv202.pdf : RealVideo 8 External Specification ; April 23, 2007 ; Version 2.02
  • RV8DecoderExternalSpecificationv203.pdf : RealVideo 8 External Specification ; July 20, 2007 ; Version 2.03
  • RV8DecoderExternalSpecificationv21.pdf : RealVideo 8 External Specification ; September 11, 2007 ; Version 2.1
  • RV9DecoderExternalSpecificationv15.pdf ; RealVideo 9 External Specification ; January 26, 2002 ; Version 1.5
  • RV9DecoderExternalSpecificationv16.pdf ; RealVideo 9 External Specification ; August 17, 2005 ; Version 1.6
  • RV9DecoderExternalSpecificationv18.pdf ; RealVideo 9 External Specification ; September 11, 2007 ; Version 1.8

  Additionally, there is an Excel spreadsheet entitled realvideo-faq.xls that appears to contain some general tech support advice for using Real’s official code. There are also 3 ZIP archives which contain profiling information about the official source code (post processing and entropy decoding top the charts which is no big surprise).

  I guess the latest version of each document (the ones dated September 11, 2007) are worth mirroring. Unfortunately, those latest document versions use a terrible font.

• Location of the amd64 compiler in Visual Studio 2022 | Compiling FFmpeg with NVENC

  6 juin 2022, par Gal Grünfeld

  I'm trying to follow Nvidia's guide to compile FFmpeg with nvenc support on Windows and it has a stage to export the path of Visual Studio's 2013 SP2 amd64 compiler to the global path variable of the compilation dev environment :

  


  


  export PATH="/c/Program Files (x86)/Microsoft Visual Studio 12.0/VC/BIN/amd64/" :$PATH

  


  


  They say earlier in the guide that for different versions of Visual Studio different path might be required. I'm trying to use Visual Studio 2022 Community, but don't know where its amd64 compiler directory is.
I also don't know what that VC stands for ("Visual C", maybe, whatever that "Visual" might mean ?).

  


  I found in the installation directory of Visual Studio 2022 a few directories named amd64 but none of them were under one with VC or something similar in its name.
The one I think is the most likely candidate to be the updated compiler is at /MSBuild\Current\Bin\amd64.

  


  If anyone knows, please tell me if if this is the right path, and if not, what is the right path.

  


  Microsoft does offer a version of Visual Studio 2013 Update 2, though (I assume they changed their naming scheme from "service packs" to "updates, which would make it the same software), but it doesn't offer a 64-bit version of it, and I want to compile a 64-bit software - so I assume it doesn't come with one. Please do correct me if I'm wrong, it'd save me needing to use a version of Visual Studio that is different than the one in the guide.