GIFs for technical drawings, keep native, do not downsample

[OPCOM]

suggestion: allow GIF image format for technical drawings, keep them in native format, do not downsample or convert to lossy JPEG.

A technical drawing to help a member might be complex (think radio set or VIC-1) and it may have features in the drawing or diagram that are 1 pixel wide. That's fine for electrical items. If the features are made too much bigger the X-Y size of a BMP or PNG file violates the data size limit. GIFs are much smaller

It is not helpful when a picture of a 27 pin connector needs all those pins explained in detail and someone has gone to the trouble to analyze the schematics for a complicated radio set like the RT-246, and label the pins of said connector as to what they do, and the uploaded GIF file gets sampled down to where the connector looks like it has dust bunnies.

I suggest that the GIF format be allowed for technical diagrams, and exempted from conversion and downsizing for the purpose of diagramming complicated things like drawings of radio connector pinouts, electronics, and the like. These kinds of things are important for members who want to do a little more than just buy the cables and hook it up stock.

It would be great if the .GIF format were:
1.) accommodated (currently it is not)
2.) allowed to be up to 1280x1024 regardless of data file size. -There won't be many.
3.) displayed in its native format and size so the user can see it correctly, or download it in its intended and legible form.

Am I right to think that no one except a dummy will use GIF for photos/pics because it is 256 colors and pictures would look bad? A GIF also consumes less data space per physical size than other formats.

If not, make a rule with a real consequence, once GIFs are freed. -GIFs to be used only for technical diagrams/drawings. or something..


other formats?
for the same file of an electrical diagram:
BMP 3MB
PNG 1M
GIF 140K
JPEG 175K and blurry
PDF? like a JPEG. It is a JPEG, a string of them, one for each page.

Vote yes for unmolested technical GIFs!

 

[gimpyrobb]

I didn't see an option for "I am too dumb to know the difference".

 

[shenkmen]

I use cutePDF to print a page or pages from a PDF to a new PDF and then upload or file for future reference. No loss and in original format. Better than a GIF.

 

[gringeltaube]

Since I found out how to easily convert a 5MB BMP-drawing into a 300KB PDF file, while maintaining the same original quality (no shadows or stains around objects, like in JPG) I'm posting both for everything I feel is worth it.


EDIT:

Update 03/31: .... so I just did some exercises converting/ saving BMP drawings (made in MS-Paint) into GIF, and back into BMP format.
I must say I'm impressed: it really works well! ... 5MB into only 220KB and back to 5MB; instantly, repeatedly x-times! It is like others already stated: only affecting (some of) the original colors but retaining clean, sharp lines and text, besides exact dimensions, of course.

So the practical use I see in this is that everyone with Windows could open (copy,paste) such a "compressed" (GIF) file (i.e. with MS-paint, which works in BMP), take measures and/or add their own mods to it and send it back as GIF, all in original quality.

I voted YES!


G.

 

[nf6x]

I am in favor of this suggestion, and here is a picture of one of my dogs.

 

[OPCOM]

Gimpy, I apologize. I did try to accommodate you.

......

When you save a GIF, like a 6 color GIF, as a JPG, you may end up with 5000+ colors. It does not play nice with the next editing session. It is because of the sampling for conversion that alternating colors become diluted based on algorithms no two of which produce results exactly alike from program to program.

The picture of the dog is now a JPG. Can we be certain the 220 colors in the JPG image are the same ones it began with?

I don't dislike the other formats, I merely want an unadulterated GIF function, pixel for pixel, color for color.

The test patterns show that in the conversion to JPG the colors have run from the blue, red, or green onto the white, and in areas with R,G, or B stipes, the stripes are no longer uniform in color. It is not so much a visual annoyance as an annoyance when cutting, pasting, and editing. It is an inaccuracy.

Also notice how the PNG file, which is a bitmap, has been degraded by local conversion to JPG, more than the JPG which may have been accepted as-is, I don't know how it works here. The PNG represents a GIF (GIF is also a bitmap) because the system does not accept GIF at this time.

 

[gimpyrobb]

I was just kidding Patrick, I know some folks are smart enough to use and appreciate high-res technical drawings and schematics. I went to school to be an injuneer, just couldn't hack the math(tensions and stresses).

 

[nf6x]

For folks who don't know the differences:

JPEG uses lossy compression. It can make small files, and it works nicely with photographs. However, it can do really bad things to things like line drawings; it doesn't deal well with sharp color transitions, and lines/text can get really blurry. Turning up the compression for a smaller file makes this effect worse.

GIF and PNG use lossless compression. Photographs often look worse and/or are much larger in these formats, but they can reproduce line drawings much more clearly than JPEG. Also, GIF does a good job of compressing line drawings, which are usually mostly white with just a small percentage of the image covered by dark lines. These formats deal ok with sharp transitions, like lines on a schematic.

The downsampling is a separate issue from the file format. Taking a 2500 pixel wide image of a schematic diagram and downsampling it to 640 pixels wide usually makes it unreadable.

 

[quickfarms]

How does PDF stack up?

 

[OPCOM]

I was just kidding Patrick, I know some folks are smart enough to use and appreciate high-res technical drawings and schematics. I went to school to be an injuneer, just couldn't hack the math(tensions and stresses).

So YOU are the guy I was copying MY math from!

Opcom,
Laser ElectroOptics Engineering Dropout
President, Mad Scientists' Calculus Haters Club

 

[OPCOM]

How does PDF stack up?

PDF is a JPEG (JPG), or in multi-page PDFs, a series of JPEGs. A PDF is a type of "container file" that holds multiple JPEGs arranged in a certain way, like one stacks coins. The free reader is designed to display both the text and images as "pictures" (and separate OCR'd text if included), and resizes the displayed pictures to your screen size or window size by resampling them in the computer's memory and then displaying the result, without modifying the original PDF file. The PDF file may also include user-created indexes and links, etc. In fact, if you select text in a PDF, then you are actually seeing a situation where each character of text is linked to a picture of that character from the document (unless the creator has substituted a standard font(s)).

In most 'full' (paid) versions of Acrobat, it can 'print' to PDF in such a way as to store or "zip" the source file.

ZIP is a method of compression which is without loss, and that is why it is used for computer files. (Zipping a bitmap of a schematic diagram can reduce it from 8MB to 1MB.)

In the old Acrobat version 5.0, I can print to PDF, and set the PDF to ZIP the source, but it is still converted to JPEG and will suffer some loss as is inherent in the JPEG format. I can also set it to compress with loss which is what most people do, otherwise the PDF can be huge. When I scan manuals for the bunkerofdoom.com site, I use the least amount of compression possible, and if the file is too big, I will compress text more, and images less. A manual operation.

One way to reduce the loss is to print at the highest resolution possible, 600DPI or more, and also print to the largest size of "paper" possible (there's no paper, but only a 'size').
So, printing a 5700x2300 2-color GIF, which is 500KB in file-size, to "11x17 tabloid" at 600DPI PDF will result in a very good image but there will still be loss.
- What is worse the resulting PDF (JPEG container) will be much larger in file-size than the original 500KB GIF.

So, why go to PDF unless the document has to be portable among diverse systems? (PDF = portable document format) Portability is an old requirement that came from old times when document-viewing software was not widely available on diverse types of computers and Adobe's claim to fame was the reader, free for every platform.
Today it's not the case for images as even the weirdest computer usually has a competent document and graphics viewer for it.

But PDF, like GIF, remains too useful to discard where things like oddball documents, coveted manuals, and textbooks are to be shared.

Just keep in mind that a truly faithful reproduction in PDF can be huge. It will easily retain the character of any notes in the margin and other "battle scars" of a hoary old technical manual, lovingly bestowed upon it by a hoary old Master Chief and his coffee cup (while he cussed the piece of gear he was repairing). - The person who scanned it might not want to go clean it up page by page. PDF will always be useful because it's about the most efficient way to do things like that where photo-like pictures and other marks are important.

Even so, most people convert scanned books to monochrome to cut the size down without losing details. Sometimes, if they are nice, they separately process any color images or cover art and insert them when they assemble the PDF document for publication.

High Quality Huge PDF Examples are here:
TM for Coast Guard URT-12 transmitter - 253MB
http://bunkerofdoom.com/mil/urt12/urt-12_manual_pub.pdf
Schematic Only - 4MB:
http://bunkerofdoom.com/mil/urt12/an_urt_12_schematic_mac.pdf

Now imagine if the 4MB schematic had been a 300K-500K GIF. My bad. Still a good read.

In conclusion, I hope that the example of a 5700x2300 GIF being only 500KB in size will be encouraging.
The GIF schematic example is here.
http://bunkerofdoom.com/kd5oei/bta250L/BTA250L_RCA1K.gif
It is a single-page scan of the schematic diagram of a 1947 RCA 1000 Watt broadcast transmitter. Nice piece o' gear even if not military. Old browsers might not open it.. too large pixel-wise. but not file-wise.