PDA

View Full Version : CRC error protection what exactly is this



Sossity
09-20-2015, 05:50 AM
CRC Error Protection adds a checksum to each frame, a decoder is able to verify each frame has not corrupted, however very few decoders use checksums.

This is what I read on the dbpoweramp website, but still a bit unsure what this means exactly, and if it is worth reconverting about 4,000 plus songs for.

what is the decoder? is it something within the batch converter? a decoder checks to be sure there are no errors in the files and fixes them during conversion? or the batch converter adds something to the files so when they are played on a player of some sort, the player will be able to decode them?

I will be using these mp3 albums on my ipod, would the CRC protection mean that the converted files had the errors fixed or have something so they there are no problems with playback on a device such as an ipod?


Also, I have a bunch of albums in mp3 that I made using the batch converter, is there a way I can check them to see if I used the CRC protection and any of the other advanced settings in the batch converter? I am talking about after the fact after they have been converted? I ask because if I want this feature on or off for the converted files I can check them before doing any re converting, it would save me time.

mville
09-20-2015, 09:02 AM
what is the decoder? is it something within the batch converter? a decoder checks to be sure there are no errors in the files and fixes them during conversion? or the batch converter adds something to the files so when they are played on a player of some sort, the player will be able to decode them?

Simply put, a decoder is software that converts your audio files to music. A CD player may have an mp3 decoder, so it can play mp3 files.


CRC Error Protection adds a checksum to each frame, a decoder is able to verify each frame has not corrupted, however very few decoders use checksums.

This is what I read on the dbpoweramp website, but still a bit unsure what this means exactly, and if it is worth reconverting about 4,000 plus songs for.

IMO, you do not need CRC Error Protection. As the website says, very few decoders use the checksum.

Sossity
09-21-2015, 03:58 AM
is there any way to check some of my already converted mp3 albums and files to see if I had the error protection feature turned on or not?

mville
09-21-2015, 10:40 AM
is there any way to check some of my already converted mp3 albums and files to see if I had the error protection feature turned on or not?

Yes. In Configure dBpoweramp >> Music Converter tab >> When Converting

do you have the Update 'Source', 'Encoder', 'Encoded By' & 'Encoder Settings' ID Tags option ticked?

If you do, have a look at the mp3 file Encoder Settings tag and it will contain the following:
-crc="1"

if you had the CRC Error Protection turned on when converting.

Sossity
09-21-2015, 07:26 PM
thank you, is there anyway to check the actual files? not in the dbpoweramp settings?

I ask because, I have a bunch of albums that I converted a long time ago with the release 15.1 version. I have now since updated to release 15.3 and have done more converting.

since I cannot go back into the configuration settings for the 15.1 version I used because I have updated to 15.3, I like to look at the songs and albums that I converted with 15.1 and see if I had used CRC, it was a while ago and I do not remember if I used it or not.

mville
09-21-2015, 08:36 PM
I'll ask again.

1. Currently, in Configure dBpoweramp >> Music Converter tab >> When Converting

do you have the Update 'Source', 'Encoder', 'Encoded By' & 'Encoder Settings' ID Tags option ticked?

2. In CDRipper >> Options >> Meta data & ID Tag >> Write ID Tags

do you have Encoded By, Encoder and Encoder Settings ticked?

... also, 3. How were your mp3 files created?

mville
09-21-2015, 08:44 PM
thank you, is there anyway to check the actual files? not in the dbpoweramp settings?

But the answer you want, depends on your dBpoweramp configuration and/or CDRipper settings. Please help me to help you. I can only do this if I have more information.

The only way I know to determine if your mp3 files contain the CRC info, is if you are writing the encoder tags to your mp3 files, hence the previous questions.

Sossity
09-22-2015, 03:11 AM
1. Yes
2. Yes
3. Mp3 files were created or converted from Flac rips of my albums, I used dBpoweramp's batch converter

mville
09-22-2015, 09:28 AM
1. Yes
2. Yes
3. Mp3 files were created or converted from Flac rips of my albums, I used dBpoweramp's batch converter

OK, look at the tags in an mp3. It should contain the Encoder Settings tag and, if you created the mp3 with the CRC Error Protection option, the Encoder Settings tag will contain -crc="1".

Sossity
09-22-2015, 11:32 AM
OK, look at the tags in an mp3. It should contain the Encoder Settings tag and, if you created the mp3 with the CRC Error Protection option, the Encoder Settings tag will contain -crc="1".

to look at the tags so far, in windows explore, or windows xp, I have just hovered my mouse over each song file, and a small bubble comes up with some details, such as album, artists, year, and the version if dbpoweramp along with bit rate etc. is this where I would see the error protection feature?

mville
09-22-2015, 12:35 PM
to look at the tags so far, in windows explore, or windows xp, I have just hovered my mouse over each song file, and a small bubble comes up with some details, such as album, artists, year, and the version if dbpoweramp along with bit rate etc. is this where I would see the error protection feature?

In Windows Explorer, if you right-click on an mp3 file, do you have the Edit-ID Tag option in the drop-down menu?

Also, do you currently edit any tags and if so, how?

Sossity
09-23-2015, 02:58 AM
In Windows Explorer, if you right-click on an mp3 file, do you have the Edit-ID Tag option in the drop-down menu?

Also, do you currently edit any tags and if so, how?

Yes there is in windows explore

Yes, I sometimes edit my tags using mp3 tag

for an experiment, I converted some flac files with crc on and some other settings, and then viewed them in windows explore, and I now see where it would indicated if an mp3 file had this setting on. So it seems now I can determine which files I had this turned on for or not.

Also, would having that feature on be of any help with reliable playback on my ipod? as of late, I have an ipod classic that was modified with a high capacity SD card and I loaded my mp3 files onto it, and most of the time they play ok, but occasionally, a song would be playing and it would freeze, or just skip to the next song.

these same mp3 files play ok in itunes and windows media player, so I suspect the problem is with the ipod. I have also had this random skipping and freezing happening on another ipod, this other one was an original ipod with its original hard drive.

I am not sure exactly what the problem is, all I can think of is maybe I should not use a usb hub for syncing the ipods, or the hardware and firmware is getting too old to be fully compatible with current itunes and dbpoweramp versions, since apple has discontinued them and support for them. Also, my music library has grown, and maybe the ipods do not have enough memory or something to handle it all. The problem is recent, as in the past I never had problems with playback on my ipods.

that is why I started looking at the CRC error feature in the batch converter, if it would help with the playback problems I have recently had with my ipods.

mville
09-23-2015, 12:35 PM
Yes, I sometimes edit my tags using mp3 tag

for an experiment, I converted some flac files with crc on and some other settings, and then viewed them in windows explore, and I now see where it would indicated if an mp3 file had this setting on. So it seems now I can determine which files I had this turned on for or not.

Great. Yes, you'll see this in the Encoder Settings tag.


Also, would having that feature on be of any help with reliable playback on my ipod?

As discussed earlier in this thread, I doubt the iPod Classic firmware decoder uses the CRC Error Protection checksum.


as of late, I have an iPod classic that was modified with a high capacity SD card and I loaded my mp3 files onto it, and most of the time they play ok, but occasionally, a song would be playing and it would freeze, or just skip to the next song.

I too have an iPod Classic, 160GB. When I got this behaviour, I had to return the iPod to Apple and got a warranty replacement. Since, then I have not had a problem with iPod Classic 160GB playing my mp3 files and I do not use the CRC Error Protection option.

If I were to get this problem again, I would probably perform a Restore in iTunes, which restores the iPod device to factory settings and deletes all data and content on it.

Sossity
09-23-2015, 05:32 PM
Great. Yes, you'll see this in the Encoder Settings tag.



As discussed earlier in this thread, I doubt the iPod Classic firmware decoder uses the CRC Error Protection checksum.



I too have an iPod Classic, 160GB. When I got this behaviour, I had to return the iPod to Apple and got a warranty replacement. Since, then I have not had a problem with iPod Classic 160GB playing my mp3 files and I do not use the CRC Error Protection option.

If I were to get this problem again, I would probably perform a Restore in iTunes, which restores the iPod device to factory settings and deletes all data and content on it.

I have done the itunes restore thing on both ipods, and the problem still happened, I dont think the song files are bad, they play back fine in windows explore and itunes, it just seems odd that it has happened on both ipods, although I have had fewer problems with my ipod classic with an original 160 gb hard drive in it. I have have had more problems with the modded ipod with the 256 gb sd card in it.

mville
09-23-2015, 06:01 PM
I have done the itunes restore thing on both ipods, and the problem still happened, I dont think the song files are bad, they play back fine in windows explore and itunes, it just seems odd that it has happened on both ipods, although I have had fewer problems with my ipod classic with an original 160 gb hard drive in it. I have have had more problems with the modded ipod with the 256 gb sd card in it.

As the restore hasn't fixed the issue, I suspect bad blocks on the HDD and SSD.

iTunes Restore does not format the entire drive. If it were possible to do a full format of the disks and to mark any bad blocks, as you would with a PC drive, this might well fix the issue. I'm not sure it is (easily) possible though.

IMO, this issue has been poorly supported by Apple and why I believe they no longer manufacture/support iPods with HDDs. It is too much of a headache for them, so they just wash their hands of the problem.

Personally, I'll just continue with my iPod and wait for a portable media player that supports micro SD cards larger than 128MB. Then, I'll be able to dump the iPod/iTunes/Apple once and for all. Believe me, it will be a blessed relief.

Sossity
09-23-2015, 07:57 PM
As the restore hasn't fixed the issue, I suspect bad blocks on the HDD and SSD.

iTunes Restore does not format the entire drive. If it were possible to do a full format of the disks and to mark any bad blocks, as you would with a PC drive, this might well fix the issue. I'm not sure it is (easily) possible though.

IMO, this issue has been poorly supported by Apple and why I believe they no longer manufacture/support iPods with HDDs. It is too much of a headache for them, so they just wash their hands of the problem.

Personally, I'll just continue with my iPod and wait for a portable media player that supports micro SD cards larger than 128MB. Then, I'll be able to dump the iPod/iTunes/Apple once and for all. Believe me, it will be a blessed relief.

thanks for your help on this, yeah it would be nice if there were other mp3 players with high capacities.

I also find itunes tends to sort weirdly, it randomly sorts artists by last name then first name, is there a way to set up an id tag at conversion to sort artists by first and then last name?

also, is there a way to check my converted mp3 albums and songs for corrupt files?

mville
09-23-2015, 09:35 PM
I also find itunes tends to sort weirdly, it randomly sorts artists by last name then first name, is there a way to set up an id tag at conversion to sort artists by first and then last name?

For me, iTunes does not exhibit any sort problems. You probably have inconsistent Artist, Artist Sort, Album Artist and Album Artist Sort tags in your flac files and so subsequently, your mp3 files. The iPod Classic firmware does have sort issues.

You could try using PerfectTUNES (unregistered version is free) ID Tags module on your flac files. This might help you identify any problems.


also, is there a way to check my converted mp3 albums and songs for corrupt files?

Yes. dBpoweramp Batch Converter >> Convert >> Converting To: Test Conversion

Sossity
09-23-2015, 11:19 PM
For me, iTunes does not exhibit any sort problems. You probably have inconsistent Artist, Artist Sort, Album Artist and Album Artist Sort tags in your flac files and so subsequently, your mp3 files. The iPod Classic firmware does have sort issues.

You could try using PerfectTUNES (unregistered version is free) ID Tags module on your flac files. This might help you identify any problems.



Yes. dBpoweramp Batch Converter >> Convert >> Converting To: Test Conversion

instead of editing my flac files in mp3 tag, could I reconvert them with id tags in the batch coverter to sort by first and last name? would the reconverted flac files lose quality?

mville
09-24-2015, 08:43 AM
instead of editing my flac files in mp3 tag, could I reconvert them with id tags in the batch coverter to sort by first and last name?

If you have the ID Tag Update utility codec installed you can edit/manipulate tags via dBpoweramp Batch Converter. Most of the time, I use an MP3Tag action for this sort of data manipulation.


would the reconverted flac files lose quality?

dBpoweramp Batch Converter >> [ID Tag Update] only edits tags and not the digital audio, so, no, the reconverted flac files will not lose quality.