Topic: HDCD (Read 8213 times)

Awesome Donkey · « **on:** January 31, 2019, 02:58:19 pm »

[ Edit by JimH -- Please see this newer thread on HDCD support in MC25. ]

HDCD works now? Nice! How do we know it's actually decoding HDCD? I don't see any mention in the audio path.

Hendrik · « **Reply #1 on:** January 31, 2019, 03:36:42 pm »

Quote from: Awesome Donkey on January 31, 2019, 02:58:19 pm

HDCD works now? Nice! How do we know it's actually decoding HDCD? I don't see any mention in the audio path.

If the HDCD field is set to On, then it'll always run the decoder. For now you need to manually set that field. In the future we'll try to detect if a title contains HDCD information during audio analysis, but thats not in yet.

Matt · « **Reply #2 on:** January 31, 2019, 03:47:47 pm »

I'll work on updating the Audio Path tomorrow.

jmone · « **Reply #3 on:** January 31, 2019, 04:27:38 pm »

Is HDCD still a thing - I thought it died out years ago?

bob · « **Reply #4 on:** January 31, 2019, 07:21:31 pm »

Quote from: jmone on January 31, 2019, 04:27:38 pm

Is HDCD still a thing - I thought it died out years ago?

I have a fair number of classical discs that are HDCD encoded and it appears others are even though they are not advertised as such...

jmone · « **Reply #5 on:** January 31, 2019, 08:30:46 pm »

Did some more reading, looks like the library is about the same as SACD so nice.

Awesome Donkey · « **Reply #6 on:** February 01, 2019, 01:47:44 pm »

Quote from: Matt on February 01, 2019, 12:58:05 pm

1. NEW: Added HDCD decoding to the Audio Path if it's engaged.

Works good.

Which brings up the question, what's the 'proper' way to rip a HDCD? I have a couple of them, and I know dBpoweramp has a feature to rip them but it rips them to 24-bit/44.1 kHz files. Should they be ripped as 16-bit/44.1 kHz instead? If I play any of the 24-bit/44.1 kHz HDCD files ripped with dBpoweramp MC says the bit-depth is wrong (which it is) so I'm just wondering how I should proceed to rip them in the future.

Hendrik · « **Reply #7 on:** February 01, 2019, 01:49:35 pm »

A 1:1 rip would have to keep them in 16-bit.

However, if the ripper detects the HDCD information, and then decides to rip them to 24-bit, it is most likely already performing the HDCD decoding.
Personally, I would prefer that, since it ensures everything will always play them properly everywhere, and HDCD decoding is no longer required.

jmone · « **Reply #8 on:** February 03, 2019, 03:20:36 am »

Quote

NEW: Added HDCD decoding to the Audio Path if it's engaged

I dug through my old CD's and I have one HDCD but I don't see it being engaged (playing from the CD itself).

Hendrik · « **Reply #9 on:** February 03, 2019, 03:29:34 am »

Its only active if you set the HDCD library field.

jmone · « **Reply #10 on:** February 03, 2019, 03:33:05 am »

OK - so couple of dumb Q:
1) How do you know if a disc is HDCD if it is not auto detected
2) How should you rip a HDCD disc once you have worked it it is HDCD

bob · « **Reply #11 on:** February 05, 2019, 12:53:54 pm »

Quote from: jmone on February 03, 2019, 03:33:05 am

OK - so couple of dumb Q:
1) How do you know if a disc is HDCD if it is not auto detected
2) How should you rip a HDCD disc once you have worked it it is HDCD

Most of them say so on the disc.
Rip it as a normal CD then set the flag in the database.

Ideally we'd like to auto-detect these. That's not implemented yet.

Awesome Donkey · « **Reply #12 on:** February 05, 2019, 12:58:22 pm »

I don't hear a difference, but I did re-rip a couple HDCDs and the HDCD decoder does kick in (after setting the flag) according to the audio path. Great work!

Having audio analysis auto-detect HDCD would be great too. Another thing that would be great to see detected (at least when ripping CDs) would be pre-emphasis (and some sort of de-emphasis filter + flag to enable it).

dtc · « **Reply #13 on:** February 05, 2019, 06:22:08 pm »

Quote from: bob on February 05, 2019, 12:53:54 pm

Most of them say so on the disc.
Rip it as a normal CD then set the flag in the database.

Ideally we'd like to auto-detect these. That's not implemented yet.

Actually, there are a lot of HDCDs that are not labeled as such. There used to be a pretty comprehensive list of CDs that were HDCD, whether or not they were listed as such on the CD. I'll see if I can find it again.

EDIT: Not the list I was thinking of but here is one list

http://www.goodwinshighend.com/music/hdcd/hdcd_recordings.htm

A good source of information on HDCD is

http://www.goodwinshighend.com/hdcd.htm

dtc · « **Reply #14 on:** February 05, 2019, 06:35:56 pm »

Quote from: Awesome Donkey on February 01, 2019, 01:47:44 pm

Works good.

Which brings up the question, what's the 'proper' way to rip a HDCD? I have a couple of them, and I know dBpoweramp has a feature to rip them but it rips them to 24-bit/44.1 kHz files. Should they be ripped as 16-bit/44.1 kHz instead? If I play any of the 24-bit/44.1 kHz HDCD files ripped with dBpoweramp MC says the bit-depth is wrong (which it is) so I'm just wondering how I should proceed to rip them in the future.

I ripped by HDCDs to 44.1/24 several years ago with dBpoweramp. I have never gotten an error playing them with MC. I have not tried them with MC 25 yet (traveling) but will when I get 25 installed on my traveling system.

Edit :with the decoded file you probably do not want the HDCD flag set since it is already decoded.

dtc · « **Reply #15 on:** February 05, 2019, 06:38:05 pm »

Quote from: Hendrik on February 01, 2019, 01:49:35 pm

A 1:1 rip would have to keep them in 16-bit.

However, if the ripper detects the HDCD information, and then decides to rip them to 24-bit, it is most likely already performing the HDCD decoding.
Personally, I would prefer that, since it ensures everything will always play them properly everywhere, and HDCD decoding is no longer required.

Agreed. That raises the issue of whether the MC ripper will be able to produce decoded files.

bob · « **Reply #16 on:** February 05, 2019, 08:05:04 pm »

Quote from: dtc on February 05, 2019, 06:38:05 pm

Agreed. That raises the issue of whether the MC ripper will be able to produce decoded files.

If you wanted them decoded you should be able to do a format conversion on the ones with the HDCD tags to 24 bit.

dtc · « **Reply #17 on:** February 05, 2019, 08:21:58 pm »

Quote from: bob on February 05, 2019, 08:05:04 pm

If you wanted them decoded you should be able to do a format conversion on the ones with the HDCD tags to 24 bit.

Somewhat round about. It would be nice to have it part of the ripper.

bob · « **Reply #18 on:** February 05, 2019, 08:50:51 pm »

Quote from: dtc on February 05, 2019, 08:21:58 pm

Somewhat round about. It would be nice to have it part of the ripper.

Since it doesn't lose anything by sitting in 16 bit format on the disk is there any reason to expand it out to 24 other than for handheld device use (which can be done on the fly)?
I'd assume too that most people are going to rip to a lossless format instead of leaving it in wav.

dtc · « **Reply #19 on:** February 05, 2019, 08:56:45 pm »

Quote from: bob on February 05, 2019, 08:50:51 pm

Since it doesn't lose anything by sitting in 16 bit format on the disk is there any reason to expand it out to 24 other than for handheld device use (which can be done on the fly)?
I'd assume too that most people are going to rip to a lossless format instead of leaving it in wav.

Take a look at Hendrik's comment above.

With dBpoeramp I rip to 44/24 flac. Then I can play it pretty much anywhere. For example I assume the HDCD decoding will not be engaged when using DLNA.

dtc · « **Reply #20 on:** February 06, 2019, 09:45:20 am »

Are you using the hdcd.exe DOOM9 software?

JimH · « **Reply #21 on:** April 09, 2019, 03:08:55 pm »

bob · « **Reply #22 on:** April 09, 2019, 07:56:37 pm »

MC doesn't use doom9 software since it's multi-platform.

dtc · « **Reply #23 on:** April 10, 2019, 06:27:59 pm »

Thanks Bob. HDCD uses peak extend, gain adjustment and reconstruction filter switching. Which of these are you implementing? Are you perhaps using the FFmpeg implementation?

Axilian · « **Reply #24 on:** April 11, 2019, 04:13:56 am »

Quote from: Awesome Donkey on February 01, 2019, 01:47:44 pm

Works good.

Which brings up the question, what's the 'proper' way to rip a HDCD? I have a couple of them, and I know dBpoweramp has a feature to rip them but it rips them to 24-bit/44.1 kHz files. Should they be ripped as 16-bit/44.1 kHz instead? If I play any of the 24-bit/44.1 kHz HDCD files ripped with dBpoweramp MC says the bit-depth is wrong (which it is) so I'm just wondering how I should proceed to rip them in the future.

If I remember when dbpoweramp rips HDCD it decodes the HDCD data so sees the equivalent of 20bit / 44 - as dbpoweramp can't encode 20/44 (nor would DACs be able to read 20/44 flac it ) it is better to encode to 24/44 (extra bits are padding) to include the extra resolution

I don't think encoding in 16/44 actually encodes the HDCD data into the resultant flac

bob · « **Reply #25 on:** April 11, 2019, 10:31:21 am »

Quote from: dtc on April 10, 2019, 06:27:59 pm

Thanks Bob. HDCD uses peak extend, gain adjustment and reconstruction filter switching. Which of these are you implementing? Are you perhaps using the FFmpeg implementation?

It's using the same one foobar uses.

carlp · « **Reply #26 on:** April 14, 2019, 06:40:34 pm »

Folks, I don't see anything about HDCD anywhere in the playback options or dsp studio. Where is the switch? Using Win 25.0.18 64bit.

JimH · « **Reply #27 on:** April 14, 2019, 07:14:26 pm »

Please try a search.

carlp · « **Reply #28 on:** April 14, 2019, 07:19:35 pm »

Where do I search?

JimH · « **Reply #29 on:** April 14, 2019, 07:21:06 pm »

The forum has a search. Google works. Just add JRiver.

carlp · « **Reply #30 on:** April 14, 2019, 07:35:04 pm »

Which only gives me this thread, which is not helpful. What "library field?" Where?

dtc · « **Reply #31 on:** April 14, 2019, 07:40:20 pm »

There is a HDCD tag. You need to select the track and check the HDCD tag for that track. You can do multiple tracks at once, like for a whole album. It has to be specifically set for each track it is to be applied to. It is not a general option that is turned on for all tracks.

carlp · « **Reply #32 on:** April 14, 2019, 07:57:39 pm »

Oh, how silly of me. It was so obvious!

Seriously, thank you.

From a usability pov, this is terrible. Hopefully, in future versions hdcd will be detected and just happen. Or be enabled where it should be, in the playback settings. Otherwise this is an undocumented function that shouldn't yet be represented as a headline feature, imo.

dtc · « **Reply #33 on:** April 15, 2019, 08:38:58 am »

Most people probably do no have any HDCDs or only a very few. The detection routine is a minor use of CPU, but no reason to run it for the vast majority of tracks. That said, there are some albums that were HDCD but not identified as such on the packaging. But those are not very common, for a format that is already not very common. Most people who know about HDCD are probably willing to identify their tracks as such.

What would be nice is a tool that scans tracks you identify and sets the HDCD tag if HDCD is found. You could run that against your whole library and be done with it. Let it run overnight if need be.

PGibby · « **Reply #34 on:** April 18, 2019, 12:38:15 pm »

Oh, cool.

I have an older DAC with hardware HDCD decoding (Sonic Frontiers). It has a light that signifies HDCD decoding or not. As long as I don't have an DSP going, HDCD lights up on an HDCD track. Obviously if I manipulate the signal at all (volume under 100%, DSP added, etc), the light goes off. I've actually used it as an indicator to getting bit-perfect audio.

Anyway...that brings me to my question:

1) With me using slight PEQ to fix a room node, would it be beneficial for me to use JRiver's implemenation of HDCD?
2) Any advantages/disadvantages of having JRiver do it vs my DAC?

dtc · « **Reply #35 on:** April 18, 2019, 01:41:32 pm »

Quote from: PGibby on April 18, 2019, 12:38:15 pm

Oh, cool.

I have an older DAC with hardware HDCD decoding (Sonic Frontiers). It has a light that signifies HDCD decoding or not. As long as I don't have an DSP going, HDCD lights up on an HDCD track. Obviously if I manipulate the signal at all (volume under 100%, DSP added, etc), the light goes off. I've actually used it as an indicator to getting bit-perfect audio.

Anyway...that brings me to my question:

1) With me using slight PEQ to fix a room node, would it be beneficial for me to use JRiver's implemenation of HDCD?
2) Any advantages/disadvantages of having JRiver do it vs my DAC?

Your DAC probably contains an HDCD chip. That type of implementation does a more complete job of decoding the HDCD encoding than most software implementations. In particular, the HDCD chip implementations has a filter stage that most software implementations do not have.

Without knowing the details of the MC implementation, it is hard to know exactly what they implemented. However, many of the software implementations are based on reverse engineering the HDCD algorithms, rather than a direct implementation based on knowing the exact HDCD specifications.

My recommendation is that the hardware implementation in your DAC probably is a more faithful implementation of HDCD than the software implementation.

That said, you need to decide if that difference is more important than fixing your room node issue.

I would listen to a well know track both ways to make a determination of the best approach to use.

PGibby · « **Reply #36 on:** April 18, 2019, 04:38:14 pm »

I'll give it a try and find out...as I just purchased the MC25 upgrade. My room mode is right at 47hz, and the only way I can defeat that in the room is PEQ (living room with kids...etc).

I suspect that taming that 47hz hump is going to be a lot more important than maintaining a bitperfect HDCD signal.

syndromeofadown · « **Reply #37 on:** April 30, 2019, 03:19:39 pm »

I don't understand how HDCD is supported.

Can we play the actual disc?
Can we rip the HDCD data from the disc?
Is there an ideal way to deal with them in MC?

I do have mine ripped to 24bit flac using DBpoweramp as that was how I found out they were actually HDCDs. I believe most were a surprise.

Any help is appreciated.

Matt · « **Reply #38 on:** April 30, 2019, 03:23:27 pm »

Quote from: syndromeofadown on April 30, 2019, 03:19:39 pm

I do have mine ripped to 24bit flac using DBpoweramp as that was how I found out they were actually HDCDs. I believe most were a surprise.

Then there's nothing more to do. We just added a decoder to expand from 16-bit to 24-bit, but if you've already done it, problem solved!

Snookboy · « **Reply #39 on:** May 20, 2019, 08:44:43 am »

I'm confused. I get setting the tag on the track/album to engage the HDCD decoder, but how do you insure it was ripped correctly? Let's say I get a new HDCD, I rip it with MC which results in a 16 bit file. I don't have the HDCD data? Is there an option with MC to rip it properly and have the data? Thanks.

qiking · « **Reply #40 on:** May 30, 2019, 08:33:17 pm »

When I choose the HDCD value in the advanced tagging it does not stay permanent. I have to re check the the value each time manually. I can play a track then go to another album and if I go back to the previous track that I checked the HDCD value it is no longer checked.

dtc · « **Reply #41 on:** May 30, 2019, 09:14:51 pm »

Quote from: Snookboy on May 20, 2019, 08:44:43 am

I'm confused. I get setting the tag on the track/album to engage the HDCD decoder, but how do you insure it was ripped correctly? Let's say I get a new HDCD, I rip it with MC which results in a 16 bit file. I don't have the HDCD data? Is there an option with MC to rip it properly and have the data? Thanks.

The 16 bit rip contains any HDCD data embedded in the track on the CD. With the tag set, on playback MC will detect the embedded HDCD data and decode it. Audio Path will indicate that the HDCD decoder is engaged. Unfortunately, playback does not tell you if it actually found any HDCD data to decode. But, if there is HDCD data in the track on the CD, then the standard rip will copy the HDCD data to the 16 bit file.

tyler69 · « **Reply #42 on:** June 08, 2019, 12:17:36 pm »

Quote from: dtc on April 15, 2019, 08:38:58 am

What would be nice is a tool that scans tracks you identify and sets the HDCD tag if HDCD is found. You could run that against your whole library and be done with it. Let it run overnight if need be.

Agree. This could also be made optional in the audio analysis.

JimH · « **Reply #43 on:** June 20, 2019, 10:38:54 am »

Please see this newer thread on HDCD support in MC25.

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Author Topic: HDCD (Read 8213 times)