pycq2002 最近的时间轴更新
pycq2002

pycq2002

V2EX 第 40693 号会员,加入于 2013-06-15 23:39:48 +08:00
pycq2002 最近回复了
2021-06-07 11:22:43 +08:00
回复了 Lavventura 创建的主题 Apple TV 关于 Apple TV 4K 的格式输出疑问
4k 60 SDR,打开匹配动态范围,动态分辨率要看你的电视支不支持检测 24p via 60 signal,下面是在 reddit 上看到的

TL;DR: It depends on your TV…leave Match Frame Rate off if your TV can do this[https://www.rtings.com/tv/tests/motion/24p].

Longwinded explanation: Most modern TVs refresh their screen 120 times per second (120Hz). The nice thing about this number is that both 24fps (for film) and 30fps (for video) map nicely (5Hz/frame and 4Hz/frame, respectively), so the TV can accurately display the source. Some TVs add "motion smoothing", and use their additional cycles to interpolate between the actual frames, and that leads to the Soap Opera Effect…that's a function of the TV, not the Apple TV, and you should disable it accordingly. ;)

Meanwhile, the Apple TV prefers to output a 60Hz signal. 30fps video is doubled (without smoothing), and then the TV doubles that again to match its 120Hz refresh rate (hopefully without smoothing), and you ultimately see 30fps.

You might have noticed that 24fps won't divide evenly into this 60Hz output signal, so the Apple TV has two options when it needs to display 24fps movies:

Use a 3:2 cadence, such that alternating frames are displayed for 3Hz or 2Hz. This is what happens when you leave Match Frame Rate off.

Switch its output signal to 24Hz, so there's a direct mapping of 1 frame to 1Hz. This is what happens when you turn Match Frame Rate on.

So…the option you choose depends on your TV.

Up until recently, 3:2 wasn't ideal, because (as you might imagine) displaying alternating frames for different lengths of time results in uneven playback (called "judder"). 24Hz was preferred, as this explicitly told the TV to display 24fps.

However, many modern TVs can detect the 3:2 cadence within the 60Hz signal, understand that it's 24fps in disguise, and adjust to properly display 24fps (with each frame getting 5Hz) on screen.

So: If your TV can do that, it's the best option…your TV won't need to switch modes as often (resulting in fewer black screens and greater stability), and the Apple TV can draw its UI at 60Hz (if it switches to 24Hz, everything is drawn 24 times per second, leading to chunky UI animations).
2020-10-20 10:11:58 +08:00
回复了 user8341 创建的主题 程序员 两道面试题
MVC 是 model view controller 的设计模式
A->B 能推出非 B->非 A ?逆否命题是等价的
2013-10-20 20:26:25 +08:00
回复了 Marthers 创建的主题 程序员 各位V友们,有用Vim或者Emacs写java的么?求好用的插件推荐
Java的话感觉还是用Eclipse之类的比较好,然后可以用Vrapper来模拟Vim键位或者装Eclim
2013-10-20 12:44:21 +08:00
回复了 sampeng 创建的主题 程序员 developer工作了5年,一点想法,给应届生一些忠告。
@livemighty 真的是同感,大多数面试公司的题目我感觉都差不多,而且网上一找都能找到答案,我就在想能通过这些面试的人估计很多都是之前背过很多面经的,我觉得真是很无聊。
@zhoubo 这个vim应该也是搞不定的把,因为python的缩进中包含了语义,vim无法判断究竟该把一句话放到哪个块里面好。
2013-08-13 21:18:36 +08:00
回复了 vopfly 创建的主题 Vim Vim7.4 released!
昨天brew upgrade直接就升级好了。。。
2013-07-31 17:08:35 +08:00
回复了 coolicer 创建的主题 Linux 我的本本装的是ubuntu和win7,如果把ubuntu换成Arch有没有可能。
Arch什么都很好,但是自从我有Syu升级挂掉之后的经历,我就又回到XUbuntu了。。。目前用了一年半还没啥问题的样子。。。
关于   ·   帮助文档   ·   API   ·   FAQ   ·   我们的愿景   ·   广告投放   ·   感谢   ·   实用小工具   ·   1492 人在线   最高记录 5497   ·     Select Language
创意工作者们的社区
World is powered by solitude
VERSION: 3.9.8.5 · 17ms · UTC 23:34 · PVG 07:34 · LAX 15:34 · JFK 18:34
Developed with CodeLauncher
♥ Do have faith in what you're doing.