Tool to extract and understand the PNG format chunks. The PNG (Portable Network Graphics) image format consists of multiple pieces of data (header, image, meta information, or hidden content).
PNG Chunks - dCode
Tag(s) : Image processing
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PNG Chunks
PNG Chunk Extraction
Tool to extract and understand the PNG format chunks. The PNG (Portable Network Graphics) image format consists of multiple pieces of data (header, image, meta information, or hidden content).
Answers to Questions
What is a PNG chunk?
PNG (Portable Network Graphics) files are composed of several parts, the chunks. Generally a file has a header, a content and an end. The PNG format also has its specification the ability to integrate a comment area chunk, compressed or not, which is usually unreadable without a dedicated software.
How to read a tEXt chunk?
The tEXt chunk is readable directly in the file (in a text editor or an hexadecimal editor), it starts with tEXt (74455874 in hexadecimal ascii), followed by a title, and a free comment area.
Example: TEXt => My Title This is a PNG comment
How to read a zTXt chunk?
The zTXt chunk is similar to tEXt except that its content is compressed with DEFLATE. Find in the file zTXt (7a545874 in hexadecimal ascii), followed by a title, and a binary area not readable directly (because compressed), that zone must be decompressed before being able to read the message.
Source code
dCode retains ownership of the source code of the script PNG Chunks online. Except explicit open source licence (indicated Creative Commons / free), any algorithm, applet, snippet, software (converter, solver, encryption / decryption, encoding / decoding, ciphering / deciphering, translator), or any function (convert, solve, decrypt, encrypt, decipher, cipher, decode, code, translate) written in any informatic langauge (PHP, Java, C#, Python, Javascript, Matlab, etc.) which dCode owns rights will not be released for free. To download the online PNG Chunks script for offline use on PC, iPhone or Android, ask for price quote on contact page !
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