Since the launch of 4K, the upgrade cost has been lower. In response to the trend, various streaming platforms have also joined the ranks of providing 4K videos. Although 4K streaming videos are very popular and are very convenient to watch on the platform, for audiophiles, Blu-ray discs are still their first choice. In concept, 4K has a higher resolution than 1080P, but this does not mean that 4K is necessarily better, especially when placed together with Blu-ray discs.
Why do 1080P Blu-ray movies look better than 4K streaming movies?
Factors affecting image quality
Terms like “4K UHD” or “1080P” simply refer to the number of pixels that make up the overall image quality. Specifically, it refers to the number of pixels per frame in a video. 4K UHD has about 8 million pixels, while 1080P only has about 2 million pixels. Although this means that technically speaking, the fine details of 4K images are 4 times that of 1080P images, this is only one of the factors in the human eye’s perception of image quality, not the only one. This is why the statement that “4K videos must look better than 1080P” itself is very flawed.
In addition to the number of pixels, there are several other factors that can have a significant impact on image quality:
- bitrate
The amount of data used to represent each video frame significantly affects image quality, with higher bitrates meaning less compression and more detail retained in the video. - color depth
The amount of color that can be displayed in a video also affects video quality. Higher color depth allows subtle color changes to be more refined and gradient transitions to be smoother, resulting in more natural and realistic images. - dynamic range
Dynamic range refers to the range of brightness that can be displayed in a video. A higher dynamic range can present more details in the dark and bright parts of the picture, making the image more realistic. - video compression
Compression is great for reducing video file size, but over-compression can lead to loss of detail, pixelation of images, and other visual degradation.
Generally speaking, Blu-ray has advantages over 4K streaming videos in terms of bit rate and color depth, which will be discussed later. At the same time, Blu-ray has lower compression than 4K streaming, which has to take network conditions into account, so you won’t see artifacts and quality is managed before Blu-ray discs are mass-produced.
The clear advantage of 4K streaming over standard Blu-ray discs is dynamic range. Only 4K UHD Blu-rays support HDR, but it’s becoming increasingly common with 4K streaming videos, which is a disadvantage of 1080P Blu-rays that don’t have HDR.
Bitrate and color depth advantages of Blu-ray discs
You’ll often see a loss of detail in dark areas in compressed video, making the whole thing look like black. The bitrate of 1080P Blu-ray discs is generally much higher than that of 4K compressed video streams, which means that Blu-ray discs can fit more data into each frame, resulting in clearer and more detailed content than highly compressed 4K streams. The extra data allows for a wider color range, more detail in shadows and volume, and less noticeable artifacts from compression.
Another advantage of Blu-ray discs is that they are not affected by network fluctuations, and you can enjoy consistently high-quality videos without the buffering or quality degradation that can occur when watching online streaming videos. Using Blu-ray discs, you can ensure a consistent image experience without worrying about network speed, bandwidth, etc.
A typical 4K stream might consume around 25Mbps, and a standard Blu-ray around 40Mbps, but don’t forget that 4K streaming video has 4 times as many pixels as a standard Blu-ray, so the bitrate advantage per pixel significantly outweighs those two numbers on their own.
Can you tell a difference in clarity after upscaling to 4K?
Whether you can see a difference between 4K and 1080P video depends on several factors, including screen size, your distance from the screen, and the quality of the video itself. If you’re sitting too far away from the TV, you might not be able to tell the difference between 4K and 1080P video because it’s harder to see individual pixels the further away you are from the screen. Video quality also affects your ability to tell the difference between 4K and 1080P. If a 4K video is heavily compressed or low-quality, it’s likely to look inferior to a high-quality 1080P video no matter where you sit.
Let’s talk about another issue: Modern 4K TVs are already very good at upscaling 1080P videos to 4K quality. In 1080P Blu-ray content, the high bitrate forces image upscaling to work hard, so the final 1080P Blu-ray can look very much like 4K in resolution, while still retaining the color depth and motion detail benefits of Blu-ray.
Blu-ray Audio is in a different league
Blu-ray audio often sounds better than typical streaming audio due to higher bitrates and less compression. Blu-ray Disc can use lossless audio formats such as Dolby TrueHD and DTS-HD, which can provide sound quality that is very similar to the original studio master. These formats use higher bitrates and less compression than typical streaming audio, preserving more detail, clarity, and depth in the sound.
In contrast, typical streaming audio is usually lossy-compressed, which means that some audio data is discarded to reduce file size. While this compression can help stream audio flow faster and smoother, it can also result in a loss of detail and a flatter, less dynamic sound.
That said, it may depend on your specific audio equipment. If you don’t have the audio equipment to take advantage of the extra clarity, you may not notice much of a difference; if your audio is played through a Bluetooth system, even Blu-ray audio will be compressed by lossy audio algorithms.
Your cherished movies and music collection are better on Blu-ray
Blu-ray will likely be the last mainstream optical format, and your only option may then be to buy or rent digital movies and albums. Of course, just like you buy lossless digital music now, you may buy a large number of digital video files with quality comparable to Blu-ray in the future. Then again, downloading 50GB of data for a movie may become commonplace in the future, but the quality of the network will affect your download, and the enthusiasm for watching the movie will slowly cool down.
However, compression technology continues to improve, so video quality comparable to Blu-ray quality may become widespread through advances in high-speed networks. We don’t know how long it will take, but one day, streaming and downloadable movies will offer better quality than Blu-ray, but there will still be other disadvantages of digital purchase, such as you are not guaranteed to watch the content forever.
Source: KOCPC Chinese