Mas essa é a questão que eu tenho colocado: porque é que são melhores leitores do que a Shield?
Mas eu tenho forma de ler 4K HDR: a Shield
Digo que é correto porque quando testo um ficheiro com espaço de cor REC709 e leio com a Sheild, o meu projetor recebe exatamente isso REC709.
Quando o ficheiro é em REC2020 SDR, o projetor recebe REC2020 SDR. Quando é REC2020 HDR10, o projetor identifica REC2020 HDR (PQ).
Resumindo, o projetor recebe sempre aquilo a que corresponde o ficheiro (lido com Mediainfo).
E acrescento: medindo as cores primárias e secundárias com imagens de teste em REC709 e REC2020 (usando um colorímetro e o ChromaPure) os resultados são também diferentes (como esperado), sendo o espaço de cor em REC2020 maior (embora uma percentagem do standard BT2020 dado que o projetor não tem capacidade para 100% do BT2020, mas é aproximadamente 100% do DCI-P3, que é maior do que REC709).
Mav
O oppo/chinoppo tem melhor chipset gráfico que a Shield, ora não fosse o Oppo considerado o melhor pelos reviewers . Sem mencionar que papa os formatos HDR todos, HDR10 , HDR10+ e Dolby Vision. Lê ISO de UHD como se fosse disco físico, e no audio igual, papa os formatos todos.
Ver um remux num oppo e na shield, comparei a trilogia dos senhores dos anéis é muito diferente na minha opinião, as cores , ao Anti-alising, motion, sem frames drops. A Shield é uma grande máquina all around , mas aquele chipset gráfico está mais optimizado para consolas e foi em parte para isso que a Nvidia a criou.
O bug que falo no BT2020 não é o de identicar correctamente, mas sim de as cores não estarem bem , estão todas bugadas pelo lixo android.
Basta veres que um dos melhores reviewers, o Vincent usa o oppo para as reviews.
Sem falar nesta borrada que a Nvidia ainda resolveu, numa box deste valor é uma vergonha:
The solution to the challenge is so-called match functions where the player matches its video pipeline and output to the content's frame rate (24, 25, 50, 60 etc) and dynamic range (SDR / HDR). The goal is to let video pass without converting it in any way. A match function can be manual or automatic. It can work on the app or system level. The optimal situation is an automatic solution implemented on the system level, which means that it will work automatically in apps running on the operating system.
Since 2017,
Apple TV 4K has - as the only TV platform - offered automatic, system-level match functions for both frame rate and dynamic range. It works with all apps that use the standard video player in tvOS but apps taking advantage of a custom video player must implement the API. However, Apple's match functions are off by default so the user must activate them first. This decision was most likely made because frame rate switching from an HDMI source involves a brief black screen every time it changes the frame frequency. This is a limitation in the HDMI standard (until HDMI 2.1's QMS). Google's Android TV platform supports frame rate switching but the important distinction here is that it is not supported on the system level and that it is not automatic. Instead, it is offered as an API - a tool for developers - that
can be implemented in apps. Unfortunately, the vast majority of streaming providers are ignoring the API at this time.
Nvidia has developed its own solution. It is a step in the right direction but unfortunately not a complete solution. The match function is manual, not automatic, so you have to manually click 'match' every time you start a new video stream. And even though the feature can be mapped to the top button on the remote control, limitations apply. Some apps crash when you try to use the match function and probably for the same reason Nvidia characterizes it as 'beta'. When it works, it works well (and also supports 24.000), but a manual function is not a solution to the challenge and it will not help 99% of users. If you opt not to use the match features you will encounter judder due to frame rate conversion in the box, depending on what you have set default output to. If you select 4K 60Hz output, European content (25/50Hz) will have judder. If you select 4K 50Hz output, American content, including movies and TV series (24fps), will have judder.
This is where Dolby Vision and the match functions collide. Dolby Vision support is a nice addition to Nvidia Shield but useless on a handful of Dolby Vision-compatible TVs, including our LG E6 OLED TV that was used for this test. The reason is that some TVs support Dolby Vision in up to maximum 30Hz. To get Dolby Vision on Nvidia Shield to function with these TVs you must set Nvidia Shield's default output to for example '4K 23.976Hz Dolby Vision and HDR10 Ready' or alternatively lower the resolution for the entire system (meaning also streaming services), for example to 1080p HD resolution. Both solutions will give you Dolby Vision but in the first example Android TV menus and all app user interfaces will be rendered in 24fps, which is unendurable, while the other example is a very big picture quality compromise. With TVs that support Dolby Vision in up to 60Hz it works as intended.
We could discuss other nuances of Nvidia's match functions but the point is that as long as it does not work automatically on the system level, and as long as there are technical limitations, it is not viable solution. Unfortunately. A few apps, including Kodi, have their own match functions implemented so if you stick to using that app only you are good, but it does nothing to rectify the situation for the rest of the streaming services on the platform. Our recommendation is therefore that you set Nvidia Shield to 4K 50Hz output if you watch primarily European content or 4K 60Hz if you watch primarily American content, movies and TV series. And then try to remember to use the manual match function whenever it makes sense.