Read time: 4 minutes
We are all aware of images and photographs profound in our lives. They serve as repositories of cherished memories, integral elements in various presentations, and much more, with their versatility being boundless. Concerning the storage of images, especially in the digital realm, concerns inevitably arise regarding their security, privacy, and the allocation of storage space. Taking care of all these factors helps avoid issues like color casting in images. In this article, we will go through the intricacies of image compression, covering three key approaches: lossless, lossy, and no compression. By the end of this discussion, you will gain valuable insights to inform your choices on capturing and storing your images, with a clear understanding of the advantages and disadvantages of each format.
Before moving further, we will define a few terms below to make things clear.
- Data Compression
Data compression, called Source Coding or Bit-Data Reduction, is the technique of encoding original information or data using a reduced number of bits, thereby shrinking its size for more efficient storage and transmission. Its significance lies in its ability to economize resources required for data handling. Compression methods can be categorized as either lossy or lossless, depending on preserving data integrity during the process. - Image Compression
It is a kind of data compression used to compress images without losing quality using visual perception and statistical properties of image data. Image compression can also be lossy or lossless. - Lossy Compression
Lossy compression selectively eliminates less critical or extraneous data by reducing the number of bits used. This compression method finds its prime utility in applications related to images, where a slight sacrifice in precision (often imperceptible) is acceptable in exchange for significantly lowering the data size. Due to the negligible perceptual impact, it called “visually lossless” compression. Notable examples of lossy compression formats include JPEG and HEIF. - Lossless Compression
Lossless compression is a data compression technique that meticulously identifies and eliminates statistical redundancies to minimize the number of bits required for storage or transmission. This method of compression finds its primary utility in scenarios where data integrity is paramount, making it ideal for archival purposes. Common applications for lossless compression encompass domains such as medical imaging, technical drawings, clip art, and comics, where preserving every detail is crucial. Prominent examples of lossless compression formats include BMP, IGA, TIFF, and DPCM. - Encoder
It refers to the device which programs data compression. - Decoder
It refers to the device which performs the decompression of data.
Compressed Vs. Uncompressed images
When capturing images with a digital camera, whether it’s a DSLR or a camcorder, you’ll often encounter a choice of image formats: RAW or JPEG (RAW Compressed). RAW offers uncompressed image data, while JPEG represents a compressed version of your photos. Your selection should align with your specific requirements or the intended use of the image. As previously mentioned, when compression doesn’t compromise image quality, it’s referred to as lossless compression. However, when compression does impact image quality, it’s categorized as lossy compression.
As previously mentioned, the fundamental purpose of image compression is twofold: to optimize storage space utilization and facilitate rapid image transmission. When viewing images on compact screens such as camera LCDs, computer monitors, small TVs, phones, or tablets, the impact of lossy compression often goes unnoticed. However, when you require large prints, expansive screen displays, high-resolution images to preserve intricate details, or a desire to maintain the original image’s integrity, capturing photos in RAW format or lossless compressed RAW format becomes essential. Professional photographers typically opt for RAW format capture, although these images are notably larger in size. Thus, it is recommended that in order to conserve space, one should save RAW images in lossless compressed form.
Digital sensors can capture an abundance of detail that surpasses what the human eye can perceive. However, during the process of image compression, when this intricate data is selectively omitted, it often goes unnoticed by the human observer. This type of compression is referred to as “lossy compression.” Images subjected to this method are particularly well-suited for tasks like emailing and web-based uploads, where efficient data handling is crucial.
Additionally, image compression serves the purpose of enhancing your camera’s ability to write images swiftly to memory cards. This streamlined process not only accelerates image transfer to your computer but also extends your continuous shooting capacity when capturing images in compressed RAW format. Furthermore, the reduced storage footprint of compressed images ensures more efficient use of available space.
Ways to avoid deterioration or loss of quality of images due to compression can be listed below:
- If your camera can capture images in RAW format, it is highly recommended to utilize this feature for optimal image quality.
- To address storage space limitations, it is advisable to invest in memory cards with larger capacities, such as those offering 64GB or more of storage space. Also, opt for external hard drives that can store more photos.
- Try to save your final image as TIFF. Format, it always compress RAW images, opt for lossless compression.
- To share a copy of an original image, use JPEG compression.
- Avoid saving your images as JPG files, as every time you open and resave a lossy compression image file like JPEG, its quality reduces.
Conclusion
In this article, we explore the differences between compressed and uncompressed image formats, helping you gain a clear understanding of which format is most suitable for preserving your images. Additionally, we address potential scenarios where saved images might face issues such as corruption, deletion, inaccessibility, or inability to open. In such cases, the easiest way to retrieve and restore them is to use an efficient and powerful Photo repair tool like Kernel Photo Repair, which works irrespective of the reasons of corruption, damage, or loss, and it can recover images from any storage device and can store them in any format. It can recover lost or deleted Sony camera images.