MP3 convert to OGG

[LumenLux]

I want to share a PTE show, but as it stands for home use, it uses an mp3 file of 55MB!

I am willing to cut mp3 quality from 128kbps to 64kbps, but am wondering if I could do best by going to OGG file?

I no longer have my original .wav file. If I convert the mp3 file to OGG, is 1, 2, or 3 best?

1. Convert my largest MP3 to chosen OGG quality.

or

2. Convert my smaller size MP3 (64kbps) to chosen OGG quality?

or

3. Convert my MP3 to .wav and then convert .wav to OGG?

With any of the above, what quality setting should I try for the OGG if I have a real need to minimize file size so show can be posted. (I am also having to compromise .jpg to smaller sizes.)

[Ken Cox]

Robert start here

http://www.vorbis.com/faq/

http://www.google.ca/search?hl=en&q=+If+I+...le+Search&meta=

ken

[JPD]

It's always better for the same bitrate with ogg (difficult to say 1, 2 or 3, I just test it was better especially on transitions), and not always, but very often smaller, but it's not a good thing if you use mp3 64 kbps to convert them in ogg, it's better to start from mp3 128 kbps or better.

There is also the THOMSON mp3PRO Audio Player (64 kbps for free version) which maybe give good files, but I am enable to tell you if it's really better as they say.

1. Convert my largest MP3 to chosen OGG quality

If I had to do it, I would chose this method.

Sorry, I forgot an answer, if possible try to don't be under 64 Kbps. Is there part of music in mono, if yes, you can make a special file in mono for this part.

[JPD]

It's possible to do sound's file smaller, but it's also often possible to have pictures' files smaller with the same quality, so PTE will be smoother.

I mean than, for instance when using Adobe, many people use the function "Save as" and not "Save for the WEB", so there are many datas in the jpg file which are unnecessary for PTE.

I recently see several slideshows where the size can be smaller of several Mo, one use 192 pictures of 720 x 480, each filesize is about 82 Ko made with Adobe (Save as, Q=8), but in these files there are for each only 60 Ko for the pictures, that mean it's possible to earn more than 4 Mo, in this slideshow, only 10 Mo are necessary for PTE, and it will run smoother and quicker.

On another one, there are 383 jpg files made with Adobe (Save as, Q=3) and the total size of the jpg files is 40 478 Ko, about 106 Ko for each picture, in which only about 69 Ko are necessary for PTE, that mean that it's possible to earn on this slideshow about 14 000 Ko, so instead to have an ogg file at 46 Kbps, it would have been possible to have an ogg file at 64 Kbps.

If you don't use "Save for the Web" in Adobe, it's always possible to use a tool as Irfanview for which there is an add-on which permit to remove unnecessary datas without changing anything to the picture.

I made some test on a picture and you can see here the relation between quality and size for Adobe and Paintshop, so you can see, for exemple that "Save for the Web Q=40" is the same real quality than "Save as Q=3 in Adobe", but the file is smaller.

Another thing, it's often difficult to know which is a quality of an ogg file, the different tools doesn't give the same information :

Q | Nominale Bitrate

------------------------

-1 | 45 kbps

0 | 64 kbps

1 | 80 kbps

2 | 96 kbps

3 | 112 kbps

4 | 128 kbps

5 | 160 kbps

6 | 192 kbps

7 | 224 kbps

8 | 256 kbps

9 | 320 kbps

10 | 500 kbps

I hope that these informations will help you.

NB The durations in non-synchronized mode are by step of 15.625 ms (64 steps for a second), so even with a very quick PC it's impossible to have a duration less than this value.

In synchronized mode it about 4 times more.

[LumenLux]

Thank you Jean-Pierre, you provide much helpful information. I will study it by tomorrow.

Regarding below, does this relate to sound, photo quality, or PTE transition speed? (And "NB" ?)

NB The durations in non-synchronized mode are by step of 15.625 ms (64 steps for a second), so even with a very quick PC it's impossible to have a duration less than this value.

In synchronized mode it about 4 times more.

I know you are very good with testing, did you produce the Quality Table in the link? Thanks again.

[Ken Cox]

NB= IMPORTANT / TAKE NOTE

http://en.wikipedia.org/wiki/NB

NB, n.b., please note – the Latin phrase Nota Bene (See List of Latin phrases#N)

http://en.wikipedia.org/wiki/List_of_Latin_abbreviations

N.B. (nota bene) means "note well". It's being replaced by "Note"

Example: "N.B.: All the measurements have an accuracy of 5% as they were calibrated according to the procedure described by Jackson (1989)."

KEN

[JPD]

I know you are very good with testing, did you produce the Quality Table in the link

I did myself this table with which we can compare jpg quality, enough long time to do, but not very difficult.

Note : please excuse-me to use N.B. I didn't know you don't use it :-)

Regarding below, does this relate to sound, photo quality, or PTE transition speed?

No, the steps' duration relate to a very quick slideshow, not for yours.