During the confinement, in Genbeta and in Xataka we were paying attention to the reduction of image quality that the main streaming services were applying so that Internet traffic did not become congested, since from the European Union they transmitted that there was a risk of reaching a lot of pressure In the net. Finally there were no problems of any kind, but quality reduction lasted longer than expected.
That gave me the idea of comparing the main services available in Spain, to see which ones offered the best bitrate and with which codec (H.265 / HEVC, H.264 / AVC, etc). The winner was clear: Apple TV +, followed somewhat by far by Disney +, Netflix and Prime Video, in that order. However, as we already discussed, the important thing was not only the number, but also the codec.
Prime Video and Netflix coincide in some contents in Full HD: according to our tests, the quality provided by Amazon in them is higher
In this sense, I have been doing tests comparing content available on Netflix and Amazon Prime Video, which They are the platforms that offer higher quality than those that have a lot of content from different producers (HBO, unfortunately, cannot be taken into account for this), and I have observed that Prime Video is better in Full HD compared to what the numbers said, thanks to the fact that it broadcasts all its contents in HEVC / H.265, opposite to Netflix, which below 4K broadcasts in the old H.264, a less efficient format and which, at the same bitrate, offers less quality.
H.264 vs H.265: what the theory says
H.264 is a high compression codec that began to be developed in 2003 and whose last version dates from June 2004. It has been key in the success of high definition, because thanks to its compression and quality over MPEG-2, the codec used in DVD, has allowed Blu-Ray and quality mass streaming video to exist.
But like everything, it ends up becoming relatively obsolete, and for 4K video a new codec was needed, the H.265 or HEVC (High Efficiency Video Coding). The H.265 has been associated with that resolution since the arrival of the first 4K TVs (really since the first generation of really prepared, because before there was no content), and is the format used in 4K Blu-Ray.
Why? The first reason is simple: it allows the space occupied by files of similar quality to be cut in half thanks to better compression algorithms. At equal bitrate or bitrate, video quality in H.265 is much better than in old H.264, and the artifacts are much less obvious.
With a lower bitrate, as we said, occupying less, H.265 is also better up to a certain ratio. It is ideal for 4K because, despite having frames four times larger than those of Full HD, with bitrates such as 15-25 Mbps, an image quality is obtained that without being that of a physical disk, it is absolutely enjoyable on Netflix, and on all on Disney + and Apple TV +. Although looking ahead there is already a new codec war, it is important to mention that H.265 is more than ready for 8K and high frame rates.
Amazon Prime Video versus Netflix: What Happens in Practice
As I said at the beginning, I have been able to carry out tests with an Amazon Fire TV Stick 4K and with an LG OLED C9 TV, both in the Fire applications and in the native TV applications. Thanks to an Amazon developer tool, when watching video b (and HDR type etc).
With this tool I have been able to verify that even old series such as ‘Stargate SG-1’, present on Amazon without even 720p resolution (640 x 360), are encoded in HEVC / H.265, as seen in the codec section of the information that the Fire Stick 4K gives. On Netflix, on the other hand, everything I have been able to test below 4K video is encoded in H.264 / AVC.
Above, using H.265 they look splendid and in 4K they beat Amazon thanks to their Dolby Vision. Perhaps with other devices there is better support, but in the many in which I have tried (also with PC and Mac laptops, and in summer with the Apple TV 4K) they tell me that reality is as I describe it.
To see what differences there are in practice, I have compared 1080p content found on both platforms, such as the film series ‘Oceans’, ‘Aquaman’, ‘Harry Potter’ and ‘V for Vendetta’, among others such as ‘Friends’, and in my opinion, the differences are very palpable, especially when viewed on televisions Large 4K.
The Prime Video apps are worse, but the image quality can make up for it. The Harry Potter saga, for example, on Amazon is in 4K HDR, while on Netflix it is only in Full HD.
Netflix boasts of its compression and achieves wonders, but the truth is that with H.264 it does not get close to what Amazon achieves with H.265 in FullHD video. It is something very evident in dark scenes, or in bright ones where there are dark areas. There, the naturalness and texture of skins at low bitrates like the ones we talked about on Prime and Netflix (4-6 mbps) is conspicuous by its absence in complicated scenes on Netflix, and it holds up surprisingly well on Prime.
It shows in sharpness, but also in artifacts. With this bitrate you can never expect wonders, but where Prime Video sometimes gives you a homogeneous and fixed image in terms of color and texture continuity, Netflix gives you a video full of moving artifacts. The difference becomes dramatic in fine detail. When there is a very intense solid color reflecting off one face of the skin, for example, Prime has a hard time showing detail, for example, but on Netflix it gets to wash off completely. Let’s see concrete examples. It is a pity that due to DRM issues we cannot take screenshots, so I have chosen to take photos of the screen trying to show the differences that I saw.
Netflix’s compression on the Full HD content we’ve reviewed destroys film-grain detail and introduces artifacts that Prime Video handles much better.
The first example is from ‘Aquaman’. First we will see the photo I took on TV playing the Amazon Prime Video version and then the Netflix version. Beyond the variables that he introduces that both photos do not come out the same, andIn the case of Amazon, I see that the skin wrinkles are more outlined, and the skin in general has more texture. In addition, in the beard you can see that Amazon retains the detail much better when compressing. In motion, the differences are more noticeable. For those who want to do the test, this is the scene where Aquaman is with his father at the bar.
In the next scene, I have captured George Clooney’s face at the beginning of ‘Oceans 11’. Without perhaps being so dramatic the difference, because for me in the first example it is, in the cheekbone that is to the left of the nose, in Amazon Prime Video I observe that the pores of the skin are clearly shown, while on Netflix, although the detail is not bad, the image comes loaded with an amalgam of artifacts I repeat, in person and in motion they are better appreciated.
In other examples of the film it is still appreciated. On this shadowed wall, in the case of Amazon Prime Video, classic film grain is seen alongside the lines on the wall, while In Netflix, in addition to not being able to appreciate the detail or the separation between the different tiles, the grain is destroyed by artifacts.
Yet another example where can be seen clearly in the letters at the bottom of the poster and in the shadow detail behind the columns.
In scenes where the camera puts the emphasis on letters on a plain background, like the one we see below, it is also perfectly observed that the text on Amazon is cleaner and more detailed (despite the fact that the photo is not good), while in Netflix the detail is smoother and text is surrounded by compression artifacts. Perhaps the Amazon shot is not appreciated too well, due to the effects of the screen that the camera captures, but the Netflix problem is perfectly observed.
In the last comparison we have made, in the first chapter of ‘Friends’, There is also much more grain in the Amazon Prime Video image than the Netflix image. We may not like the film grain, but the reality is that the Blu-Ray from which the videos of both platforms are extracted contains that grain and is how the series was recorded, so it reflects reality much better. We can see it both in the face and in the yellow jacket and in the blue garment.
Since I first saw Friends in high definition, which was on Netflix, i thought the image contained a lot of artifacts on the faces and they were heavily washed, at once. Phoebe’s face is the perfect example to realize this.
In summary, it would be appreciated if Netflix could encode all its contents again to offer them in H.265 or in more modern codecs such as AV1 or H.266, because in movies and series from a few years ago and today it offers a lower image quality. And it is not a trivial topic. During the quarantine, many people complained about Netflix’s image quality outside of 4K, and we already know that it was not because it was not 4K, but because at an already limited quality, they applied large bitrate reductions, which weighed down greatly the experience.
If the content is 4K, no problemThere, those of Reed Hastings do it very well and offer Dolby Vision where Amazon only offers, in general, HDR10.