You will most likely encounter this image format if you work in the typography and printing industry or anywhere with scanners. It is also quite popular among photographers. Let's find out why it has earned its reputation as a flexible and versatile image format and what are its strengths and weaknesses. So let's look at...
What is the TIFF
TIFF stands for Tagged Image File Format, it can store raster image data and identifies by .tiff or .tif extensions (.tif exists just for older computers that were able to read file extensions with only three characters). This format was created by Aldus Corporation jointly with Microsoft and was originally released for scanners in the mid-1980s. Not least, it was an attempt to create a common format for scanned images instead of a diverse bunch of formats. Later in time, Aldus Corporation was acquired by Adobe inc. which is currently holding the copyright of the TIFF. TIFF is cross-platform and has a versatile and extensible structure.
Let's look now at what in its structure makes it so versatile and extensible.
Structure of TIFF
TIFF files generally consist of three parts: the Image File Header (IFH), the Image File Directory (IFD), and raster data. The Image File Header always locates at the beginning of the file. In contrast, the Image File Directories and raster data can be in any part of the file. One Image File Directory and linked to it raster data codes information about one image. This way one TIFF file can contain plenty of images.
Let's now look at what actually makes TIFF so universal — tags. Tags are data structures located in IFD consisting of a name and value; they contain information about associated raster data. This information is usually about color maps, dimensions of images, type of compression, and other characteristics of raster data.
The image below shows several options for the location of IFDs.
In essence, every Image File Directory is a kind of guideline for all the information about the associated image in a TIFF file.
Compression
TIFF can be either uncompressed or compressed and supports different compression algorithms. Usually, it uses lossless algorithms such as
- PackBits run-length encoding scheme (PackBits RLE),
- CCIT Group 4,
- Lempel-Ziv-Welch (LZW).
However, lossy algorithms such as JPEG also can be applied. Virtually TIFF is a kind of container where different bitstream encodings can be placed for raster images.
Let's now look at why this format is a good one.
Advantages
The main advantages of TIFF are:
- it serves as a container in which other encodings can be put, like JPEG, and can store many images;
- it is pretty good for images with deep color depth and high spatial resolution, in particular scans;
- while TIFF supports lossy compression, its main use is with lossless one, which means that images will keep their original features;
- it can store multiple images in a single TIFF, for example, a number of pages of some document;
- TIFF is a cross-platform format and works in all major operating systems.
Let's now look at what makes this format not the best choice for some tasks.
Disadvantages
Because of keeping all the information about images, TIFF files can be quite large and take up more space on your drive than other alternatives. Also, it is more difficult to share or send such big files and it makes them not suitable for some areas like website design. Note that there is a 4 GB size limit, which prevents its use when you need extremely big files. Also, it lacks standardized tags for vector or text drawings.
Conclusion
As you can see, TIFF is actually not a very new image file format, but it is still great in use, especially in the printing industry. Its main advantages are lossless compression, the ability to store multiple images in one file, the capacity to store high-resolution images with high color depth, and also it works in all major operating systems. The main downside is that an image saved as a TIFF file is larger than almost any other image format, so you better use it wisely. Overall, TIFF might be a good choice if you work with scanned pictures, and high-resolution pictures while editing if you need to keep all the information or pictures which will be sent for printing.