Noncompliant cue sheet pregaps not working right when burning from FLACs

[tgies]

Hello,

I have a reproducible issue where ImgBurn 2.5.8.0 is doing something weird with EAC's noncompliant cuesheets that have pregaps placed in the end of the preceding track's file (edit: only when burning from FLACs via directshow decoding. If I pre-convert my FLACs to WAV I do not have the problem). I have attached a sample cuesheet where Track 4 has a pregap.

When using ImgBurn, the CD burned from this cuesheet exhibits the following problems:

• Old portable CD audio players and some car stereos etc. cannot skip to/past the affected track correctly (some I have cannot seek to track 4; others can seek to track 4 but not to track 5.)
• Some of those same players will play past track 4 if allowed to play through to the end, but will display "track 4" the whole time.
• Attempting to seek within track 4, the timer display on the stereo is incorrect (e.g. starts counting from -9:59, or starts from 0:00 every time)
• ImgBurn's own "media analysis" function seems to hang on track 4, but it does eventually get through it -- though it shows NO pregap on track 4.

When I burn from the same cuesheet with EAC's write CD function, everything is fine and I get the CD I expect, and moreover ImgBurn's analysis function shows the pregap that's supposed to be there.

I believe I have ruled out the CD burner (tried several) and media (ditto) as the cause of this problem. I have burned these same cue sheets with other software over the years without issue.

This looks like possibly a related issue to the one this person had years ago.

sample.cue

Edited March 8, 2020 by tgies
figured out it had to do with the FLACs

[tgies]

Here is a different example. This one is a bit odd because track 3 has a pregap which burns correctly. The missing pregap problem (and the attendant seeking issues on stereos) happens at track 5.

sample2.cue

[tgies]

OK, sorry to keep replying to my own thread, but get a load of this: It has something to do with whether the source file needs DirectShow decoding or not. My source files are FLACs. When I pre-convert them to WAV using flac.exe, changing nothing else, and burn from the same cuesheets, I don't have a problem.

I'm using this package of dshow filters.

So I'm speculating the problem here relates to the padding calculation that ImgBurn does when the directshow filter does not hand back the exact number of audio frames expected.

Edit: Have now tried the DC-Bass dshow filter pack and I appear to no longer have this issue. Will now observe a moment of silence for the ~12 CD-Rs I blew through figuring this out.

Edited March 8, 2020 by tgies
problem doesn't happen with DC-Bass