When is PNG better than ODD?
PNG images are very detailed, support solid and volumes of other colors, and retain high image quality with lossless compression. In contrast, ODD images support limited color profiles and are less detailed than PNG.
These features make the PNG image format ideal for various digital images, including graphics and photographs, which require detailed backgrounds and colors.
When is ODD better than PNG?
ODD images are scalable, proprietary, and open-source file formats, while PNG is a bitmapped file format that loses quality and res with upward or downward scaling. Thus, ODD is suitable for web-based and stand-alone office suites and individual apps, like word processors, spreadsheets, and presentations.
The pros of ODD images are that they can be scaled up or down with image details preserved, they can be easily converted to other file formats, such as PDF and Microsoft Word, and they are cost-effective because they are open-source and widely supported by all web browsers and most operating systems, software, or platforms.
ODD vs. PNG Table Comparison
| Element | PNG | ODD |
| Transparency | Supports transparency | Supports transparency |
| File Size | Larger than ODD; size limit of 2G x 2G pixels | Smaller than PNG; a size limit of 128x128 pixels |
| Image Quality | Pixelated with scaling but retains all image details with lossless compression. | Scalable without losing resolution level; high-quality images. |
| Performance | Larger ODD needs more bandwidth and loads slowly. | It is smaller, has less bandwidth, and loads faster. |
| Structure | It starts with an 8-byte signature header with many chunks having interior fields depending on the kind of chunk. | It has a single XML document and many sub-documents with custom, user-defined, and pre-defined metadata. |
| Animation | It hardly supports animation or lively animated content | Supports animation or scenes rendering 3D objects |
| Storage | Larger, necessitating more storage space than ODD. | Smaller than PNG, necessitating less storage space. |
| Compression | Huffman coding and LZ77 lossless compression. | ZIP lossless compression with DEFLATE algorithm |
| Browser Support | Supported by almost all browsers except IE6. | Universally supported by all old and new browsers. |
Differences and similarities between PNG and ODD images
ODD and PNG file formats are identical in browser support, image quality, transparency support, and lossless compression. ODD differs from PNG in animation support, file size, structure, performance, and storage.
Transparency
ODD and PNG files support transparency. The ODD file’s texts and structure assume the XML format with the specified color scheme, which can be viewed without special tools. The file format uses its ability to encrypt lossless files with an alpha channel that permits information to be transparent.
ODD's XML-aware devices can conveniently show the hierarchy of color elements in an ODD file. It supports documents, including presentations, spreadsheets, and word processors, with diverse transparency intensities, color depths, and ranges.
Conversely, PNG supports transparency through the alpha channel, indicating the transparent backgrounds of all pixels. Often, its transparency level ranges between 0 and 255 pixels, representing the transparent and opaque levels, respectively. The tRNS auxiliary chunks, in turn, take control of PNG’s transparent structure.
File Size
PNG files are significantly larger than ODD files. A PNG file has no size limit and can be as large as 140GB and above. Besides, the maximum file dimension of a PNG image is 2Gx2G pixels. The lossless PNG files are detailed and retain all image data after compression, making them relatively larger than ODD files.
The ODD file consists of multiple images with varying color depths and sizes, giving rise to larger file sizes but comparatively smaller than PNG files. PNG files are raster graphics and not scalable, while the vector-based ODD file sizes can be reduced or increased significantly through scaling to fit any screen size.
Each ODD document and sub-document has a maximum file dimension of 128x128 pixels. The lossless ODD ZIP compression with DEFLATE algorithms is similar to Huffman’s DEFLATE lossless compression algorithms. The compression methods significantly reduce ODD and PNG file sizes.
Image Quality
PNG is a high-quality file format known for its lossless compression. ODD is a file format that allows upward or downward scaling, retaining image details or resolution levels, similar to vector graphics. In contrast, scaling a PNG image up can make it blurry or indistinct due to its raster nature. However, ODD and PNG retain color with lossless compression, justifying their high-quality standing.
While ODD files are high quality, they are assumed to have limited color depth compared to PNG. The ODD file format supports a Wide Color Range with 8 bits per color channel, resulting in over 16 million colors, but it does not support ICC profiles for color management. ODD version 1.2 permits legacy algorithms with unusual bit depths of 128 bits, 196 bits, and 256 bits.
On the other hand, the PNG file format supports 24-bit RGB or 32-bit RGBA color space. PNG also supports 256 quantized palette colors and TrueColor files with 16 million colors, providing a robust color depth similar to the assumed capabilities of ODD files.
Performance
PNG files require more bandwidth to be shared online, leading to slower web responsiveness than ODD files. Their large size also limits user experience and reduces search optimization.
ODD format performs better online than PNG. Its comparatively smaller files enhance website performance, resulting in optimized search engines and better user experience than PNG.
Structure
A PNG file starts with an 8-byte signature, followed by chunks with a uniform syntax. The IDAT chunks containing the compressed image data are read sequentially from the beginning to the end of the file.
ODD is a vector graphic format that stores drawing data in an XML-based structure. This format allows for two types of document structures: a single XML document or a collection of sub-documents, each representing different components of the drawing data.
When comparing the two formats, PNG's raster nature results in pixelation when scaled images, whereas ODD's vector nature allows for scaling without losing quality. They both support transparency, but only PNG supports two-dimensional interlacing. Structurally, PNG files use a chunk-based binary format that is read sequentially. In contrast, ODD files use a text-based XML format with sub-documents, providing more flexibility in data representation and metadata inclusion.
Animation
PNG files hardly support animations but have extendable specifications that can be integrated into the APNG file format. Such specifications support animated PNG or animation by including the animation control chunk. ODD supports animations and scenes rendering 3D objects through specific lighting and projection. Although smaller, their animated images are less info-rich, colorful, and appealing than animated PNGs.
Storage
The compressed ODD files are stored in a manifest file. This file, which has the pathname META-INF/manifest.xml, stores various information, including styles, settings, meta, content, and Thumbnails. The storage period for these file formats depends on the handling process or conditions they are subjected to.
In contrast, losslessly compressed PNG files preserve all file details, making the file format comparatively larger than the ODD format. This necessitates more storage and bandwidth for file sharing. Losslessly compressed PNG files can last forever when stored in the cloud, base64 encoding, CDN, and file systems.
Compression
Both PNG and ODD file formats use lossless compression. ODD employs the ZIP lossless compression technique, organizing its contents into an archive containing many files and directories with binary data. This process begins with the encryption and compression of XML file contents using the DEFLATE algorithm, retaining the archive structure. A checksum of each file section is calculated for password verification during encryption. User-entered password in UTF-8 encoding is generated and applied to the package component. ODD’s compression method significantly reduces file size more than PNG while maintaining high quality.
PNG also uses lossless DEFLATE compression, which combines LZ77 and Huffman coding algorithms. DEFLATE can be adjusted from 0 (non-compressed) to 9 (fully compressed). The compression process involves two phases: filtering and compression. During filtering, delta encoding is applied to each scan line of pixels. The filtered data is then compressed using DEFLATE, ensuring the original image can be reconstructed. Despite its efficiency, DEFLATE in PNG often results in larger file sizes than ODD’s compression.
Browser Support
ODD is the second most popular XML-based open standard file format on the web, followed by PDF. Thus, it enjoys universal support from older and new web browsers, including Chrome, Firefox, Edge, Brave, Discord, Safari, Internet Explorer, and Opera. No browser is reported to be incompatible with ODD files.
PNG, on the other hand, now enjoys 81.8% support from top web browsers. It is compatible and supported by Chrome, Firefox, Opera, Safari, Discord, Edge, and Brave. However, Internet Explorer lacks inherent support for PNG files or images.
Converting PNG to ODD or ODD to PNG
Users may want to convert PNG to ODD since ODD files are mostly compatible with different operating systems and browsers, are an open-source file format (cost-effective), and can be easily converted using online tools like Convertjack.
Alternatively, web browsers, designers, or developers may be prompted to use an ODD to PNG converter called Convertjack to convert their ODD to PNG since PNG files are detailed and information-rich, have sharp edges and solid colors, are excellent for image editing, and are widely supported across platforms and browsers.