Jpeg Compression Ratio

Teo · 12th October 2005

The E300 having selection of 1/2.7, 1/4 .....compression when using Jpeg.
Is there such selection to no any compression for Jpeg or how to?

TIA
cheers

hammer_400 · 12th October 2005

from adrek wrotniaks review....

# JPEG compression: selectable as 1:8 (standard), 1:4 (HQ) and 1:2.7 (SHQ). I consider this a good choice, and Olympus is quite conservative in naming these settings.

For comparison, the Canon EOS 350D uses two compression settings, named Fine (1:6) and Normal (1:11). The Nikon D50 allows for three settings; Fine (1:4), Normal (1:8), and Basic (1:16), obviously more objective naming than Canon's.

We can see that the worst quality setting in Olympus cameras is close to the best one in the Canon, and to the middle one on the Nikon. This should be taken into account when comparing writing speeds and continuous shooting rates.
---------------------------------------------------------------------------------------------------

i think jpeg is already a compressed format.. uncompressed n lossless would be tiff or RAW...
spo far i think only the 1dsMKII ans 1dMKII can select compression from 1-10...
But compared to the other consumer dslrs got 1/2.7 already very good liao...

chancy · 12th October 2005

Hello Teo,

The very format of JPEG itself incorporates compression, users are allowed to select various compression levels with trade-offs between file size & image quality. Image information is decarded when an image is saved when the JPEG format is seleted or resaved.

A non-compressed JPEG image isn't JPEG at all.

Hope this explains.

Cheers,

ykkok · 12th October 2005

For non compressed, use TIFF.

LittleWolf · 12th October 2005

Originally Posted by chancy

The very format of JPEG itself incorporates compression ...
A non-compressed JPEG image isn't JPEG at all.

Lossless JPEG does exist, but very little software supports it. (It is very different from the common lossy JPEG scheme.)

Much more interesting for photography would be the use of 12-bit JPEG. It would solve a lot of problems in processing JPEG images (namely posterization). Unfortunately, manufacturers appear to ignore it.

AReality · 12th October 2005

Originally Posted by chancy

A non-compressed JPEG image isn't JPEG at all.

Hope this explains.

Cheers,

A "JPEG" is a type of format, there is no such thing as a "non-compressed" JPEG. There is however, a "lossless" JPEG compression.

ykkok · 12th October 2005

What we really mean by TIFF is the mode currently available in Olympus camera.

RAW and TIFF is the current only lossless format in Olympus camera.

JPEG2000 format does support 'lossless' mode, but not really widely supported at least for now. This is some kind of compression format similar to 'Compressed TIFF' that we usually see in PC's software.

The reason for using standard lossy JPEG is to 'lose' some detail in returns for huge space saving.

AReality · 12th October 2005

just to add on,
RAW and TIFF are totally different.

RAW is the quantized and binarized data taken from each photosite.
TIFF is a 24-bit(varies) data for each pixel in the image.

Teo · 13th October 2005

Really appreciate for all the advise.
THANKS!!

ykkok · 13th October 2005

TIFF is the only non-compressed option straight from the camera where you can deliver for printing.

Even if you shoot in RAW, if you want the best possible printing, develop those RAW into TIFF and send for printing, especially larger format.

12th October 2005	#1
Teo Member Join Date: May 2002 Posts: 422	Jpeg Compression Ratio The E300 having selection of 1/2.7, 1/4 .....compression when using Jpeg. Is there such selection to no any compression for Jpeg or how to? TIA cheers

12th October 2005	#2
hammer_400 Member Join Date: Nov 2003 Location: Sg Posts: 692	Re: Jpeg Compression Ratio from adrek wrotniaks review.... # JPEG compression: selectable as 1:8 (standard), 1:4 (HQ) and 1:2.7 (SHQ). I consider this a good choice, and Olympus is quite conservative in naming these settings. For comparison, the Canon EOS 350D uses two compression settings, named Fine (1:6) and Normal (1:11). The Nikon D50 allows for three settings; Fine (1:4), Normal (1:8), and Basic (1:16), obviously more objective naming than Canon's. We can see that the worst quality setting in Olympus cameras is close to the best one in the Canon, and to the middle one on the Nikon. This should be taken into account when comparing writing speeds and continuous shooting rates. --------------------------------------------------------------------------------------------------- i think jpeg is already a compressed format.. uncompressed n lossless would be tiff or RAW... spo far i think only the 1dsMKII ans 1dMKII can select compression from 1-10... But compared to the other consumer dslrs got 1/2.7 already very good liao... Last edited by hammer_400; 12th October 2005 at 09:45 PM.

12th October 2005	#3
chancy Member Join Date: Dec 2003 Location: Northern Singapore Posts: 556	Re: Jpeg Compression Ratio Hello Teo, The very format of JPEG itself incorporates compression, users are allowed to select various compression levels with trade-offs between file size & image quality. Image information is decarded when an image is saved when the JPEG format is seleted or resaved. A non-compressed JPEG image isn't JPEG at all. Hope this explains. Cheers,

12th October 2005	#4
ykkok Member Join Date: Feb 2004 Posts: 531	Re: Jpeg Compression Ratio For non compressed, use TIFF.

12th October 2005	#7
ykkok Member Join Date: Feb 2004 Posts: 531	Re: Jpeg Compression Ratio What we really mean by TIFF is the mode currently available in Olympus camera. RAW and TIFF is the current only lossless format in Olympus camera. JPEG2000 format does support 'lossless' mode, but not really widely supported at least for now. This is some kind of compression format similar to 'Compressed TIFF' that we usually see in PC's software. The reason for using standard lossy JPEG is to 'lose' some detail in returns for huge space saving.

12th October 2005	#8
AReality Senior Member Join Date: Jun 2003 Posts: 4,392	Re: Jpeg Compression Ratio just to add on, RAW and TIFF are totally different. RAW is the quantized and binarized data taken from each photosite. TIFF is a 24-bit(varies) data for each pixel in the image. __________________ . The Visual Journalist

13th October 2005	#9
Teo Member Join Date: May 2002 Posts: 422	Re: Jpeg Compression Ratio Really appreciate for all the advise. THANKS!!

13th October 2005	#10
ykkok Member Join Date: Feb 2004 Posts: 531	Re: Jpeg Compression Ratio TIFF is the only non-compressed option straight from the camera where you can deliver for printing. Even if you shoot in RAW, if you want the best possible printing, develop those RAW into TIFF and send for printing, especially larger format.