Converting AIFF files to WAVE does it improve sound

[audiventory]

Entire library of 2000 CDs were ripped in a AIFF. See a trend that many people find wave files sound better. Those who have stored original libraries in FLAC may have the benefit of a better conversion to AIFF then I have. Can I convert my AIFF files to WAVE with similar improvements that FLAC to a AIFF can offer?

 

Is WAV and AIFF identical audio file formats.

WAV and AIFF based at one file structure.

WAV and AIFF difference in byte order in samples and number values into non-audio data blocks. These blocks also have other format than WAV.

Order bytes is legacy of used hardware platform.

 

For quality of sound AIFF, WAV, FLAC are absolutelly same, because contains identical audio data.

 

Theory what unpacking/repacking cause additional CPU load and hence noise while have no practical proofs.

[audiventory]

Try and listen,

if you think it sounds better, be happy and convert

 

Agree.

[audiventory]

try to embed different pictures into the same song file, the same song will always sound different.

 

Metadata and audio data are located in different places of audio file. They don't intersect.

 

Audio player read metadata (and display it) just open file for reading. Before playback.

 

After it audio player read audio data from file.

It can place it to computer memory in full size or portion-by-portion.

 

So reading metadata and playback audio are divided by time. Hence it is uncorelated processes.

 

As alternative, drawing of artwork may be performed as parallel process, but it consume milliseconds of processing time once and performed independently on reading playback buffer into DAC.

[audiventory]

37 minutes ago, yamamoto2002 said:

6 years ago, I benchmarked byte reordering code for AIFF reading and found my not-so-optimized code converts AIFF (715MB, contains entire CD PCM) to little-endian byte order in 0.11 second on my Mac Mini Mid 2010.  Computer is very good at byte reordering task.

 

ARM processors used for mobile phones have dedicated SIMD instruction for this task, VREV16 instruction that reorders 4 big-endian PCM samples to little-endian in one instruction on one CPU core!

 

Of course better avoid any swaping and data arrays transfers.

 

But 0.11s/715 MB is nothing comparing filtering or resampling

 

Also comparing operations (if/else) consume many resources.

 

I mean C/C++ languages.

 

 

[audiventory]

Yamamoto2002,

May be on C/C++ you get better results.

Personally I don't work with C#, but my friends says (who came to C# from C for faster development), what it is not most fast language for signal processing.

[audiventory]

On 21.03.2017 at 9:08 PM, Jud said:

 

Wasn't this MS's attempt to develop a Java equivalent?  Java is not noted for its speed either.

 

Yes. It was intended as crossplatform decission.

 

I don't follow this platform business development. Probably now, it is reality.

 

I'm more interesting in product creation than useles learning new programming technologies, that permanently obsoleted :-)

 

I take new programming technologies, if it obviously promiss me big step forward.

[audiventory]

23 hours ago, Ralf11 said:

RTOS used to be a good OS for signal processing - but that was long ago in a different universe

 

It is interesting issue.

 

RTOS (guaranteed reply time of system on event) in audio have no big sense.

 

Because, if system have no computing resources, RTOS can't work.

 

If system have resources, all time issues solved via buffering in RAM and in DAC's buffer. "RTOS" work in usual DAC here :-)

 

RTOS systems need for cars, plans, robots, etc. For allications that demands guaranteed time of reply on event (changing wheel position on changing sensor condition, as example).

[audiventory]

6 hours ago, mansr said:

 

Your bottleneck is almost certainly I/O, at least in any realistic scenario.

 

As rule, the bottleneck in "if ... then ... else..." constructions first.

 

If no other very obvious way, need minimize condition control.

 

After it need minimize memory copy places (there conditions checked too).

 

Though need begin from local/portional code-execution time measurement.

 

Other wise many efforts may be wasted.

 

Sometimes no sense optimize something, if it work good for user or many efforts increase performance too small.

 

6 hours ago, yamamoto2002 said:

Of course there are another opinion there, some people think it is some sort of unscrupulous to run inefficient code because it is waste of energy resource

 

It may be solved via one time pre-conversion to format/form what played back in bit-perfect mode without/with minimum "on fly" processing.

[audiventory]

15 hours ago, Jud said:

 

I suppose cross-platform stuff can't be the most efficient because it requires a compatibility layer.  So if you need speed, you use something else.

 

Absolutelly, Jud.

However, exists way for C language. Qt library, as example. There even compatibility with QNX (RTOS, that Ralf (@Ralf11) mentioned above).

 

When I began in 1990s C/C++ programming, we many efforts spent to display-plot graphics. Now it is not matter for DSP applications.

 

13 hours ago, Ralf11 said:

back in ye olden days, people would test the code to see where the bottlenecks were, then redo those modules in assembler... 

 

Yes. I don't written Assembler modules, but I inserted Assembler fragnmets code to C code.

 

In my youth I tried write compiler of Assembler for one-chip computer without elementary knowledges about compilers. But I don't finished this work.

[audiventory]

13 minutes ago, mansr said:

 

For tight processing loops, yes. What we're talking about here is essentially a file copy, and there the disk I/O dominates unless it's a RAM filesystem.

 

For arrays copying used "for ..." construction with conditions.

 

How to implemented memcpy (standard C-library function), I don't learned. May be it work in assembler more optimal way than universal "for ....".

 

Disk input/output resource consuming depend on how work with it: size transferred data, buffering, reading in parallel thread, etc.

 

I don't know that points of time measurement @yamamoto2002  done: with accounting disk operations or without.

 

Anyway for each OS and library need check the time performance.

[audiventory]

4 hours ago, mansr said:

 

Even if the flash itself is infinitely fast, those still entail an additional DMA operation at PCIe rate. In reality, the fastest SSDs achieve transfer rates up to a few GB/s.

 

When you made music projects in DAW and old computer with old "mechanical" HDD, there disk load about zero even for high resolution 96/192 kHz in float point and more 10 audio tracks + midi tracks. Each track is separate audio file, midi tracks placed in single file.

 

But CPU load may be about 100% for DSP. After DSP off, CPU load decreased to 10%.

 

It is significantly harder mode, than read 1 file from disk.

 

It is approximate values. Many depend on certain disk, system settings, reading buffer length. Theoretically it need check for every computer.

 

I suppose, consuming resources for input/output disk is not significant in total time of calculations.