For some of us captions are a necessity, not a nicety.
We are only 5 miles from the ATSC 3 transmitter but 50 miles from the ATSC 1 transmitters which are subject to breakups and dropouts - some days unwatchable.
Please elevate the priority on caption support.
Thanks..
I also get Captions on my Android s21 Ultra ... What is your client ... I am on the Latest Firmware from silicondust.
I'm using Channels DVR to connect to my Silicondust HDFX-4K (10A5433A).I love it but am consistantly missing captions on most of my local ATSC 3.0 non encrypted stations. My Channels client on both FireTV and iPad consistantly show captions on 103.1 & 108.1 but never on any of the other non encrypted stations (110.1, 115.1, 145.1, etc.)
As a troubleshooting measure I ran the HDHomerun client on both the same FireTV and iPad connected directly to the HDFX-4K (10A5433A). On the HDHomerun client I can see captions (tiny useless captions at the bottom of the screen but captions never the less) on all my non encrypted ATSC 3.0 channels. That makes me think the the captions are being transmitted by the local channels but the Channels DVR software is not allowing them to pass on most of my non encrypted ATSC 3.0 channels. The symptom is consistant and reproducable. Any information or advice would be welcome. Thanks
TL;DR – The captioning method used for ATSC 3.0 is new, and Channels does not yet support it.
ATSC3 captions are A/343, which is roughly the same as TTML. However, Channels does not currently support TTML captions for decoding.
Some stations transmit the same CTA-708 captions that ATSC1 uses in tandem with the A/343 captions that ATSC3 requires. On those broadcasts, Channels can display those captions.
Unfortunately, until the underlying libraries that Channels uses support TTML captions, full native ATSC3 captions will not be available in Channels.
Thank you for the reply and answer. I will no longer search my setup for a reason that I am not getting ATSC 3.0 captions and will continue to otherwise enjoy using Channels DVR. That said I have to say my adventure into ATSC 3.0 has been a disappointed. At every turn I find that ATSC 3.0 is at an experimental stage and very much a work in progress.
You are not alone in that feeling. I was all set to dive in but the more I learn the less I want to. I do have the luxury of strong ATSC 1.0 signals though.
Chris
Comskip has the Option to extract CC into SRT when it runs ... So why can't the developers give us the option to extract the CC and use them... I believe they already support SRT Subtitles.. That is what I do on my other DVR Software.
Might work might not but worth a try. All my Captions work on every ATSC 3.0 Channels so I cannot really test this... using FireTV Max 2nd Gen.
output_srt=1
Comskip uses the same libraries that Channels uses. Neither Comskip nor Channels presently support TTML subtitles.
I guess my ATSC 3.0 Networks do not use this type of CC as they all work on all channels. Thanks for the info.
TTML subtitles are required in ATSC3. However, some stations are additionally embedding CTA-708 closed captions in the video stream (as required by ATSC1). Your ability to use closed captions from ATSC3 feeds within Channels means your broadcasters are either doing both, or transmitting non-compliant streams.
In ATSC1, subtitles were delivered as part of the video stream. In ATSC3, subtitles are a wholly separate stream alongside the video and audio streams.
I guess the below doesn't really gives any Info about CC.
General
ID : 1 (0x1)
Complete name : LEGO Masters S04E05 Cirque du Soleil 2023-10-26-2059.mpg
Format : MPEG-TS
File size : 2.05 GiB
Duration : 1 h 1 min
Overall bit rate mode : Variable
Overall bit rate : 4 783 kb/s
Frame rate : 59.940 FPS
FileExtension_Invalid : ts m2t m2s m4t m4s tmf ts tp trp ty
Video
ID : 49 (0x31)
Menu ID : 3 (0x3)
Format : HEVC
Format/Info : High Efficiency Video Coding
Format profile : Main [email protected]@Main
Codec ID : 36
Duration : 1 h 1 min
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Active Format Description : Letterbox 16:9 image
Frame rate : 59.940 (60000/1001) FPS
Standard : Component
Color space : YUV
Chroma subsampling : 4:2:0 (Type 0)
Bit depth : 10 bits
Color range : Limited
Color primaries : BT.709
Transfer characteristics : BT.709
Matrix coefficients : BT.709
Audio #1
ID : 50 (0x32)
Menu ID : 3 (0x3)
Format : AC-4
Format/Info : Audio Coding 4
Commercial name : Dolby AC-4
Format version : Version 2
Codec ID : 6
Duration : 1 h 1 min
Channel(s) : 6 channels
Channel layout : L R C LFE Ls Rs
Sampling rate : 48.0 kHz
Frame rate : 29.970 (30000/1001) FPS (1601.6 SPF)
Compression mode : Lossy
Delay relative to video : -132 ms
Language : English
I-Frame interval : 30 frames
Number of presentations : 1
NumberOfGroups : 1
Number of substreams : 1
Presentation #1 : 5.1 Main (English)
Presentation ID : 0
Dialogue normalization : -24.00
Language : English
Loudness : Yes
Integrated loudness (speech gated) : -24.7 LKFS
Integrated loudness (level gated) : -24.9 LKFS
Audio Loudness Standard : Manual
Realtime loudness corrected : Yes
Dialogue corrected : Yes
Dynamic Range Control : Yes
Home theater AVR : Film standard
Flat panel TV : Film standard
Downmix : Yes
LoRo center mix gain : -3.0 dB
LoRo surround mix gain : -3.0 dB
LtRt center mix gain : -3.0 dB
LtRt surround mix gain : -3.0 dB
Group #s : 1
Group #1 : Main
Content classifier : Main
Language : English
Channel coded : Yes
Number of substreams : 1
Substream #s : 1
Substream #1 : 5.1
Channel mode : 5.1
Channel layout : L R C LFE Ls Rs
Preprocessing : Yes
Phase 90 filter info : Not applied
Surround attenuation known : Yes
LFE attenuation known : No
Dialogue enhancement : Yes
Enabled : Yes
Max gain : 9 dB
Channel configuration : C
Audio #2
ID : 51 (0x33)
Menu ID : 3 (0x3)
Format : AC-4
Format/Info : Audio Coding 4
Commercial name : Dolby AC-4
Format version : Version 2
Codec ID : 6
Duration : 1 h 1 min
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 48.0 kHz
Frame rate : 29.970 (30000/1001) FPS (1601.6 SPF)
Compression mode : Lossy
Delay relative to video : -33 ms
Language : Spanish
NOK : tools_metadata
I-Frame interval : 30 frames
Number of presentations : 1
NumberOfGroups : 1
Number of substreams : 1
Presentation #1 : Stereo Main (English)
Presentation ID : 0
Dialogue normalization : -24.00
Language : English
Loudness : Yes
Integrated loudness (speech gated) : -23.1 LKFS
Integrated loudness (level gated) : -23.7 LKFS
Audio Loudness Standard : Manual
Realtime loudness corrected : Yes
Dialogue corrected : Yes
Dynamic Range Control : Yes
Home theater AVR : Film standard
Flat panel TV : Film standard
Group #s : 1
Group #1 : Main
Content classifier : Main
Language : English
Channel coded : Yes
Number of substreams : 1
Substream #s : 1
Substream #1 : Stereo
Channel mode : Stereo
Channel layout : L R
Preprocessing : Yes
Previous Mix Type 2-ch : Pro Logic
Phase 90 Filer Info 2-ch : Not applied
Dialogue enhancement : Yes
Enabled : Yes
Max gain : 9 dB
Channel configuration : L R
Menu
ID : 48 (0x30)
Menu ID : 3 (0x3)
Format : HEVC / AC-4 / / AC-4
Duration : 1 h 1 min
List : 49 (0x31) (HEVC) / 50 (0x32) (AC-4, English) / 57 (0x39) () / 51 (0x33) (AC-4, Spanish)
Language : / English / / Spanish
Try the Channels DVR mediainfo using the File number of the recording.
Here's an example from my File 7256
http://127.0.0.1:8089/dvr/files/7256/mediainfo.json
notice ----->"closed_captions": 1 in the h.264 video stream
{
"chapters": [],
"format": {
"bit_rate": "4312623",
"duration": "1801.678755",
"filename": "/shares/dvr/TV/Rick Steves' Europe/Rick Steves' Europe S12E03 2023-10-15 Rick Steves Europe Ancien 2023-10-30-1600.mpg",
"format_long_name": "MPEG-TS (MPEG-2 Transport Stream)",
"format_name": "mpegts",
"nb_programs": 1,
"nb_streams": 4,
"probe_score": 50,
"size": "971245312",
"start_time": "45575.763256"
},
"m3u8_up_to_date": true,
"streams": [
{
"avg_frame_rate": "60000/1001",
"bits_per_raw_sample": "8",
"chroma_location": "left",
----->"closed_captions": 1,
"codec_long_name": "H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10",
"codec_name": "h264",
"codec_tag": "0x001b",
"codec_tag_string": "[27][0][0][0]",
"codec_type": "video",
"coded_height": 720,
"coded_width": 1280,
"color_range": "tv",
"display_aspect_ratio": "16:9",
"disposition": {
And Mediainfo does display them as EIA-608/EIA-708 for this one
Text #1
ID : 4193 (0x1061)-CC1
Menu ID : 452 (0x1C4)
Format : EIA-608
Muxing mode : SCTE 128 / DTVCC Transport
Muxing mode, more info : Muxed in Video #1
Duration : 30 min 0 s
Start time (commands) : 12 h 39 min
Bit rate mode : Constant
Stream size : 0.00 Byte (0%)
Language : English
Text #2
ID : 4193 (0x1061)-CC3
Menu ID : 452 (0x1C4)
Format : EIA-608
Muxing mode : SCTE 128 / DTVCC Transport
Muxing mode, more info : Muxed in Video #1
Duration : 30 min 0 s
Start time (commands) : 12 h 39 min
Bit rate mode : Constant
Stream size : 0.00 Byte (0%)
Text #3
ID : 4193 (0x1061)-1
Menu ID : 452 (0x1C4)
Format : EIA-708
Muxing mode : SCTE 128 / DTVCC Transport
Muxing mode, more info : Muxed in Video #1
Duration : 30 min 0 s
Bit rate mode : Constant
Stream size : 0.00 Byte (0%)
Language : English
Text #4
ID : 4193 (0x1061)-2
Menu ID : 452 (0x1C4)
Format : EIA-708
Muxing mode : SCTE 128 / DTVCC Transport
Muxing mode, more info : Muxed in Video #1
Duration : 30 min 0 s
Bit rate mode : Constant
Stream size : 0.00 Byte (0%)
No, because as stated above, ATSC1–style closed captions are actually a part of the video stream.
Subtitles for teletext, DVDs, DVB, and most everything else (including ATSC3) are generally transmitted as a separate stream alongside the A/V content; in ATSC1 the subtitles are part of the video component.
{
"chapters": [],
"format": {
"bit_rate": "4784553",
"duration": "3689.168811",
"filename": "Y:\\ChannelsDVR\\TV\\LEGO Masters\\LEGO Masters S04E05 Cirque du Soleil 2023-10-26-2059.mpg",
"format_long_name": "MPEG-TS (MPEG-2 Transport Stream)",
"format_name": "mpegts",
"nb_programs": 1,
"nb_streams": 4,
"probe_score": 50,
"size": "2206378080",
"start_time": "35119.138100"
},
"m3u8_up_to_date": true,
"streams": [
{
"avg_frame_rate": "60000/1001",
"chroma_location": "left",
"closed_captions": 0,
"codec_long_name": "H.265 / HEVC (High Efficiency Video Coding)",
"codec_name": "hevc",
"codec_tag": "0x0024",
"codec_tag_string": "[36][0][0][0]",
"codec_type": "video",
"coded_height": 1080,
"coded_width": 1920,
"color_primaries": "bt709",
"color_range": "tv",
"color_space": "bt709",
"color_transfer": "bt709",
"display_aspect_ratio": "16:9",
"disposition": {
"attached_pic": 0,
"clean_effects": 0,
"comment": 0,
"default": 0,
"dub": 0,
"forced": 0,
"hearing_impaired": 0,
"karaoke": 0,
"lyrics": 0,
"original": 0,
"timed_thumbnails": 0,
"visual_impaired": 0
},
"duration": "3689.035344",
"duration_ts": 332013181,
"field_order": "progressive",
"has_b_frames": 5,
"height": 1080,
"id": "0x31",
"index": 0,
"level": 123,
"pix_fmt": "yuv420p10le",
"profile": "Main 10",
"r_frame_rate": "60000/1001",
"refs": 1,
"sample_aspect_ratio": "1:1",
"start_pts": 3160734441,
"start_time": "35119.271567",
"time_base": "1/90000",
"width": 1920
},
{
"avg_frame_rate": "0/0",
"bits_per_sample": 0,
"channel_layout": "5.1(side)",
"channels": 6,
"codec_long_name": "AC-4",
"codec_name": "ac4",
"codec_tag": "0x342d4341",
"codec_tag_string": "AC-4",
"codec_type": "audio",
"disposition": {
"attached_pic": 0,
"clean_effects": 0,
"comment": 0,
"default": 0,
"dub": 0,
"forced": 0,
"hearing_impaired": 0,
"karaoke": 0,
"lyrics": 0,
"original": 0,
"timed_thumbnails": 0,
"visual_impaired": 0
},
"duration": "3688.818467",
"duration_ts": 331993662,
"id": "0x32",
"index": 1,
"r_frame_rate": "0/0",
"sample_fmt": "fltp",
"sample_rate": "46034",
"start_pts": 3160722429,
"start_time": "35119.138100",
"tags": {
"language": "eng"
},
"time_base": "1/90000"
},
{
"avg_frame_rate": "0/0",
"codec_long_name": "binary data",
"codec_name": "bin_data",
"codec_tag": "0x50505453",
"codec_tag_string": "STPP",
"codec_type": "data",
"disposition": {
"attached_pic": 0,
"clean_effects": 0,
"comment": 0,
"default": 0,
"dub": 0,
"forced": 0,
"hearing_impaired": 0,
"karaoke": 0,
"lyrics": 0,
"original": 0,
"timed_thumbnails": 0,
"visual_impaired": 0
},
"duration": "3689.168811",
"duration_ts": 332025193,
"id": "0x39",
"index": 2,
"r_frame_rate": "0/0",
"start_pts": 3160722429,
"start_time": "35119.138100",
"tags": {
"language": "eng"
},
"time_base": "1/90000"
},
{
"avg_frame_rate": "0/0",
"bits_per_sample": 0,
"channel_layout": "stereo",
"channels": 2,
"codec_long_name": "AC-4",
"codec_name": "ac4",
"codec_tag": "0x342d4341",
"codec_tag_string": "AC-4",
"codec_type": "audio",
"disposition": {
"attached_pic": 0,
"clean_effects": 0,
"comment": 0,
"default": 0,
"dub": 0,
"forced": 0,
"hearing_impaired": 0,
"karaoke": 0,
"lyrics": 0,
"original": 0,
"timed_thumbnails": 0,
"visual_impaired": 0
},
"duration": "3688.685000",
"duration_ts": 331981650,
"id": "0x33",
"index": 3,
"r_frame_rate": "0/0",
"sample_fmt": "fltp",
"sample_rate": "46034",
"start_pts": 3160731438,
"start_time": "35119.238200",
"tags": {
"language": "spa"
},
"time_base": "1/90000"
}
]
}
Says "closed_captions": 0, Yet I get Close Captions playing.
Great, you've discovered an error/bug in how Ffmpeg/Avcodec reports CCs in H.265 streams. (Maybe you can document your situation and file a bug report.) The output you posted shows 4 streams:
Just because your output shows that the stream does not contain closed captions, your experience shows it obviously does. (Also, the manner of how CCs are embedded has evolved since the beginning of digital transmission. Perhaps whichever flag that is being flipped for CCs is checking for a previous method, rather than the current method.)
In short, if you see CCs on ATSC3 feeds, they are from ATSC1–style CCs. At present, Channels does not support ATSC3 subtitles.
It appears that data stream is the subtitles.
The MIME type of the subtitle track listed in the MPD is application/mp4, the @contentType attribute is text, the @codecs attribute is stpp for TTML-based samples and wvtt for VTTCue samples.
From
I have been Prety Lucky with ATSC 3.0 ... in my area they removed DRM on allChannels and I get Captions.
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