Audio and Subtitle Internationalization support

[R. Linden]

Could we kindly request equal support for Internationalization on subtitles and audio tracks, similar to what the Apple Media Framework, also known as Core Media, allows? Presently, distinguishing between Spanish (Spain) and Spanish (Latin America), for instance, is not feasible. Without this differentiation support, constructing high-quality video streams with distinct audio and subtitle tracks becomes quite challenging. Subler is currently the sole open source project I am aware of that addresses this requirement precisely.

On ffprobe side using the following command:

ffprobe -print_format json -export_all true -show_streams -show_format -loglevel quiet -hide_banner file.mp4

will only return the language without the Internationalization extension ("language": "spa"):

{

"index": 8,
"codec_name": "mov_text",
"codec_long_name": "MOV text",
"codec_type": "subtitle",
"codec_tag_string": "tx3g",
"codec_tag": "0x67337874",
"id": "0x9",
"r_frame_rate": "0/0",
"avg_frame_rate": "0/0",
"time_base": "1/1000",
"start_pts": 0,
"start_time": "0.000000",
"duration_ts": 7936544,
"duration": "7936.544000",
"bit_rate": "47",
"nb_frames": "2571",
"extradata_size": 48,
"disposition": {

"default": 0,
"dub": 0,
"original": 0,
"comment": 0,
"lyrics": 0,
"karaoke": 0,
"forced": 0,
"hearing_impaired": 0,
"visual_impaired": 0,
"clean_effects": 0,
"attached_pic": 0,
"timed_thumbnails": 0,
"captions": 0,
"descriptions": 0,
"metadata": 0,
"dependent": 0,
"still_image": 0

},
"tags": {

"creation_time": "2022-12-17T20:40:49.000000Z",
"language": "spa",

}

},

Thanks in advance

[R. Linden]

Subler showing internationalization support for individual audio, subtitle and video track elements of a mp4 file