What encoding is this for Gif image? - encoding

I wanted to download an image from the web. But when I 'save image', it opens as a .txt file. I figure this is some type of encoding for the image but I can't find out which.
I want to eventually automate downloading the image for further processing, specifically text recognition. I've tried to convert the .txt using some online base64 encoders/decoders with no success. However, https://convertio.co/ was able to convert the .txt to .gif but I don't know how it did what it did.
I've given a sample of the .txt file. The actual file is much bigger.
The file name beings as such (if it helps):
data:image;base64,R0lGODlhyABGAIMAAPRDNvRDNvRDNvRDNvRDNvRDNvRDNvRDNvRDNvRDNvRDNvRDNvRDNvRDNvRDNv///ywAAAAAyABGAAAE+vDB (and it goes on, its very long).
GIF89aÈ�F�ƒ��ôC6ôC6ôC6ôC6ôC6ôC6ôC6ôC6ôC6ôC6ôC6ôC6ôC6ôC6ôC6ÿÿÿ,����È�F��úðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|úðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|úðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|úðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ|ðÁ;
I can see that there are '|' characters in between. May be for separating pixels.
The entire file is here: https://pastebin.com/BPbTHMZ7


It's seems to be a GIF image encoded as a data URL:
data:image;base64,R0lGODlhyABGAIMAAPRDNvRDNvRDNvR...
This format can be used in HTML and CSS file and is handy because the image data is directly embedded in the HTML/CSS file and does not need to be loaded with a separate request.
The start of the text basically says it's data URL, containing data for an image and the image is encoded using Base 64.
To decode it:
Chop off the start of the text, namely data:image;base64,.
Run the remaining text (R0lGODlhy...) through a Base64 decoder. The result will be binary data.
Save the binary data to a file using a file name with the extension .gif.
Now you have a proper GIF image as a file.

Related

What are the characters shown on a file after forcefully changing the extension?

Recently I changed the extension of an .apk file to .txt and despite this, I was able to open it on Notepad with some random characters, that weren't available on the keyboard in the file. org/antlr/runtime/ANTLRFileStream.class…TmOÓP=w[×QËÀ)ê|A…ÑETÔ¢NP¢™ãË—º•Q3ZÓcüþ¿j",£ß4ñGÏmÇñ˽Ïs{žçœçeûùëóW ±¨á0F5d0ÖA˔‹LÈã’ŠËR˜PqEƒ†Iy\•ØkÒºÞÁЂ´¦TL«˜H­95{ÙÚ°2K/­×–Y³Üªù(ð·:%œv\'¸!Гû÷óðª#¢èUܵä¸öòæÆÛ_±^ÔÂt^Ùª­Z¾#ýæc"XwêKž_5-7¨ù¦¿éΆmÞZ^Y*ÍS “ÛÖ¹µ¹7eûUàxn]%µ‘Ð^TÊvË^…kžUˆ;u_àTw<sÁ}µDL%ÛªØ>ùÄš#º…Rø˜¨;o)\,0ǚԞ݇ؓ‡àΪ<ò6ýr³¥GsÃ횪EOÌ_…É =è•Ç¬Ž#8ª£½ú^fùõ˜Ž›¸%pü IT{`Á2þ¶<Š:î`NÇ<î긇A˜èÿïˆ8Ç0Q¥»¨#- Ze7srRÉšíVƒõÐ]0rí&tÀ”O´‡[Y±K ö¬H›¯Ü %÷¬8Ì) r+åšW·ÑÏF†¿,bd—i%h³­ˆá8½YÄiª‘
Not just this, but while converting many other extensions like .jar,.xapk, etc. would show me these characters.Can anyone please explain, what factors are these characters based on, and how does the OS decides or try what characters to show in an unsupported file exactly.
Is there a way to get the original content through this data?

Lets say you created a text editor, which can write and save text files as well as open text files. you also defined the encoding that will be used to save text in binary files(all files when saved are binary). So your encoding looks something as following:
Your encoding Emacs encoding
TEXT BINARY TEXT BINARY
A 01000001 ă 01000001
B 01000010 Ћ 01000010
... ...
Z 01011010 Ϡ 01011010
lets say you create a file with 'ABZ' as its contents. this file when saved contains value 010000010100001001011010. When you open this file with your text editor, the editor finds 010000010100001001011010 as file contents and using above encoding it knows that its 'ABZ' hence it prints 'ABZ' on the screen.
Now lets say you open same file using emacs, since emacs uses its own encoding it displays "ăЋϠ", There is nothing wrong with emacs. it just doesn't know that data was written using your custom encoding.
So the point is that every file is written in a specific format, for example APK format can only be correctly understood by Android system. when you try to open the APK file in a text editor it just tries to make sense of binary data in the same way as emacs does in above example.
Is there a way to get the original content through this data?
If you know the originally encoding using which data was written, then you can read the contents of file using same encoding.

Starting format for text file to be converted to other formats

I need to write a document using images, texts, hyperlinks... And then convert it to PDF and DOC (but in the future it can be converted to more file formats).
What's the best "starting format" for this document?

Doc or Docx might be the best file format for creating the document containing images, texts, hyperlinks, and many more elements. Once created, it's easy to convert files in .doc/.docx format into other file format, such as Image, PDF, HTML, by using OpenXML or even commercial library like Spire.Doc.

How to create mat file containing video in it

I'm new to matlab programming.I have an image processing code which helps to load a mat file in it. the code accepts .mat file as input with video file in it.
filename=('C:\Users\HP\Desktop\Folder\Image\NVR_ch2_main_cut_35-41.asf');
s=load(filename);
s=struct2cell(s);
M=double(s{1});
if (length(size(M))==4)
M=squeeze(M(:,:,1,:));
end`
Error using load
Unknown text on line number 1 of ASCII file C:\Users\HP\Desktop\Folder\Image\NVR_ch2_main_cut_35-41.asf
"Seh".

Just use v = VideoReader(filename) instead of the load function.
For further information: http://ch.mathworks.com/help/matlab/ref/videoreader.html

Well obviously Matlab won't read your file because it contains things load won't accept.
Does your file comply to this: (from the Matlab reference , next time you should read this)
ASCII files must contain a rectangular table of numbers, with an equal
number of elements in each row. The file delimiter (the character
between elements in each row) can be a blank, comma, semicolon, or tab
character. The file can contain MATLAB comments (lines that begin with
a percent sign, %).
http://de.mathworks.com/help/matlab/ref/load.html#responsive_offcanvas
Read your first sentence. You say you want to load a .mat file. But filename ends with .asf which is some video format if I remember correctly.
You can't feed a video file into load.

Add exif date to jpeg using filename

I have a bunch (about 1200) of jpg/jpeg files, which have a filename pattern of: IMG-YYYYMMDD-WA####.jpg or .jpeg. None of them have any exif data. I would like to (batch) add exif dates (created, modified, ...) using the date pattern in the filename. Time doesn really matter for me.
I have searched this (and other) forums, but i cannot find anything related to ADDING these dated to jpeg files. I was hoping someone here could help me out.
EDIT: Using Linux (Mint 17,1)

This should not be difficult to write. What you need to create is a filter that:
Removes the existing JPEG file APPn header
Inserts an EXIF header with the date.
You would not need to mess with the compressed data at all. You're going to need to read a bit of the JPEG standard, just enough to get an idea of the block structure. Do a byte-by-byte copy until you hit an APPn marker.The APPn markers have byte counts so you know how much to skip over. Insert your own EXIF marker into the stream. Then copy the rest of the data.
You're need to read the EXIF standard to figure out how to format the header.

iTextSharp - Problem while extracting images with CCITTFaxDecode

I am using iTextSharp to extract images from PDF. However, if the images are CCITT fax decoded, the bitmap creation fails with "Parameter not valid" error.
As PdfReader.GetStreamBytesRaw returns CCITT encoded bytes, bitmap creation fails.
Can someone please help me with decoding CCITT encoded bytes and in turn create a bitmap out of it?
Thanks,
Chandru

I found a workaround to get bitmap from CCITT encoded PDF files.
Ghostscript supports converting PDF files to Tiff. There is a simple C# wrapper available to convert PDF files to jpg files here.
http://www.mattephraim.com/blog/2009/01/06/a-simple-c-wrapper-for-ghostscript/
The wrapper can be easily modified to get CCITT compressed Tiff files instead of jpg files.
The wrapper supports converting a specific page of PDF to Tiff.
The solution is, convert the specific page of PDF to a temporary tiff file, load the bitmap from the tiff and delete the tiff file.
Chandru

but in your answer get resolution and i will get resolution from original image in pdf