Principle of Time of Flight 3D Camera

https://upcommons.upc.edu/bitstream/handle/2117/13573/1232-Lock-in-Time-of-Flight-(ToF)-Cameras_-A-Survey.pdf

A near-infrared light (NIR), via light-emitting diodes (LED), is emitted by the system

and then reflected back to the sensor. Many authors [9]–[12] provide formulations for sinusoidal signals, although other periodic functions can be used. Every pixel on the sensor samples the amount of light reflected by the scene four times at equal intervals for every period, (m0,m1,m2 and m3 in Fig. 1), which allows for the parallel measurement of its phase

Conservatism vs Liberalism

https://www.youtube.com/watch?v=tN9bu6CP318
There are some good arguments in this youtube but they all miss their points.

The lecturer repeated say that being in that University is a privilege.
For ordinary listener, you do not realise the implication of what he is saying.

It is not easy to go to that university. It means that, even though you have money, you may still not be able to get into that university. Which is not the whole truth. You may not have money to pay tuition fees.

What listeners do not realise is that money is not taken into account  by that lecturer. He assumes that only academically deserving students are allowed in that university.

Why would they argue about placement? It is about affirmative action policies in USA, where places in a university is reserved to minorities or races that had been subjected to discrimination.

The lecturer argued that affirmative action is completely wrong because a deserving student will lose places to a less qualified student and correcting racial discrimination in the past is completely wrong. Which is exaggerated. Just becasue you cannot catch all criminals, does not mean that we should abolish all criminal laws.

In ethical considerations, facts must be observed and exaggerations avoided.

Affirmative action policies can still be implemented despite discriminatory practises just like income tax policies, in order to maximise the resources of the nation and increasing the livelihood of its citizens.

One simple way is to stick to academic results, instead of ability to pay. In that way, the standard of education does not drop. So scholarship money should be given to people who really cannot afford it, and it should be paid back or bonded with work obligations.

Giving monetary rewards to best achievers has some good but it should not be overdone.

There are other issues that should be addressed. What is important is to stick to facts.

There are other videos spread by these conservative groups that are the backbone of President Donald Trump. If we have time, we should try to listen to them and understand their viewpoints.

Response to Facebook's Ridiculous Censorship

You have given a very dangerous precedence.

Paranoid responses are allowed but explanations of the actual meanings of the phrases are not allowed.

How could you allow people to insult national languages and the name of a country, and when people responded, you complained that it is racist.

It is like the Jews in Israel killing innocent Arabs, and when we commented that the Jews in Israel killed Palestinians, it is condemned as racist, because it incites hatre. Bloody idiot. You are hiding the truth in order to hide hideous racist crimes.

Racism should be tackled with truth, not paranoid. We cannot just disallow any condemnations of a person of a certain race, and consider it as racism, and therefore allow worse responses such killing them for complaining against a member of the race.

My post that had been deleted is such a clear example. A Malay guy was insulted by a racist chinese salesgirl who insulted his language and country, that happens to be the language of the country that the girl is staying and supposed to be loyal.

To add salt to injury, she offered alcohol to everyone at a public place, without any approved license. You do not serve alcohol at a supermarket. Only display canned or bottled drinks.

In response to that insults he asked if the girl is chinese.
Is that racist, if we are to ask for someone's race? Yes, to racist bastards like chinese and jews.

Because the chinese in Malaysia believed that they were insulted by being called racists, they justify a really racist actions of terminating his employment and threatening his children that study in a chinese school. Actions are what constitue racism. Not insults against individuals.

Facebook may have a duty to protect harmony but do you want to protect harmony of child rapists, murderers and racists? Why should we care if we insult them and their actions? In fact, it is our duty to insult these bastards so that they realise the consequences of their actions.

Stopping an article because it hurts the feelings of others is also stupid. Because many people feel insulted if they are proven wrong. So, should we stop all posts that try to explain all the wrongs in the world? This is what FAcebook is doing right now through its idiotic reviewers.

When a Malay wants to insult people, he will use the word "babi" or :"pork" but why should the pork eaters feel insulted. It is just like people calling others as beef eaters, or shark eaters etc. Are you insulted if you are called with such names? You will be an idiot if you are.

Worse, there are ulteriour motives behind being insulted, which I detected as extreme racism, i.e. getting excuses for the blatant racism that the chinese in Malaysia exhibits.

As to "cina keturunan babi" insulting to the chinese race, this is completely false. The Malays will use the same insult to any person of any race, because the Malays consider "babi" as dirty.

In Malay, the phrase "cina", translated as chinese, does not refer to a race but a person. It is just the way the Malay grammar is interpreted. Malays like to use this kind of insult when directing to a person, even to its own race, Melayu bangsat (Malay bastard) does not mean that the entire Malay race is bastard. The race is put as an idicator that he is a traitor for his race by being a bastard.

If you start interpreting pig, or "babi" as an racist insult, then you should start disallowing others animals as well, such as crocodile, shark, etc. It is just ridiculous how people can be so sensitive.

We cannot allow guilty people get away with murder just because people express their displeasure towards them in a truthful way.

You may read more about my analysis of the possibly insulting phrase at:
https://othmanahmad.blogspot.com/2018/12/is-cina-keturunan-babi-racist-and.html

Is “cina keturunan babi” racist and incite hatred?

To some people yes.

But to these people, to be called “cina” or “chinese” is already racist and insulting.

Our official policy now is to consider it as insulting, but it is only applied in West Malaysia.

In Sabah, where I live most of the time, this is not the case. We identify them with their races and sub divisions. Again, this is only true in the Eastern part of Sabah. In the West Coast, the Kadazans, part of the Dusun tribes have a strong movement in creating a strong ethnic group KadazanDusun.

A lot of Malaysians consider Sabah as a model of racial tolerance. My theory is due to our pride in our individual identities. This is again not true for Filipinoes in the West Coast or those in West Malaysia. They felt insulted when asked about their race, and I suspect they lied about their true races.

My belief is that for true racial harmany, we just need to be honest. Lying will only complicate matters and leads to racism. Categorising races in Malaysia as Malay, Chinese, Indians, Natives will only lead to frictions among the races. These major divisions are created to enhance unity in each of these divisions so they lie about their races in order to gain legal advantages.

That is why even facebook allows people to consider calling anyone chinese as insulting and racist. I think similarly for Jews. It is not surprising when you consider that the founder Mark is a Jew and his wife Chinese.

This is ridiculous. It is not according to facts and logic. It will be disastrous sooner or later.

What actually is racism?

Prejudice, discrimination, or antagonism directed against someone of a different race based on the belief that one's own race is superior.

‘a programme to combat racism’

https://en.oxforddictionaries.com/definition/racism

So any antagonysm is considered racist, even the truth. so catching a thief of a different race is called racism? Certainly not correct but widely used. Especially by chinese and jews, and this facebook reviewer.

https://en.m.wikipedia.org/wiki/Racism is better.

Racism is the belief in the superiority of one race over another, which often results in discrimination and prejudice towards people based on their race or ethnicity. 

Racism cannot be used against one individual of a race.

In Malay, the word “cina” alone refers to an individual or a country. To refer to a race, we must attach the adjective “bangsa”, or “race”.

“keturunan babi” means “descendents of pig”. It is a deregatory word used by Muslim Malays against anyone who eat pork. It can be applied to all other races, including, non Muslim Malays.

Is it deragotary, but not racist. It is applied to many races. Ok, you may call it anti-religion but it does not apply to vegetarians. It is just the view of one religion over the others. I am sure vegetarians do not look kindly to all the carnivorous humans.

From the perspective of the chinese or pork lovers, can it ever be deregatory?

For example, I love eating fish, even sharks. Do I feel threatened when labelled as shark-eaters?
The speaker may think it is deregatory, but for me, it is an honour. Sharks may be our enemies, but its strength and speed in water is something to be admired.

So why should the chinese feel insulted when called "descendents of pigs"? They love eating pork, so they must be proud of pigs. If the chinese feel insulted, it is just they are too senstive and look for excuses to feel insulted. Just like being insulted when called chinese.

Going back to the word "cina" that looks like it is referrng to a race. I have explained that it is directed to a person. 

https://www.roketkini.com/2015/08/17/wahai-najib-bangsa-melayu-bukan-bangsa-bangsat/
Malays like to insult other Malays with the word "Melayu Bangsat".

It does not mean that entire race is bangsat (very bad, unprincipled). Only that he is a traitor to the Malay race.
So when we say, Cina Bangsat, it means the chinese who betrayed the chinese race by being bangsat, not the whole race.

Similarly for the Cina Keturunan Babi. He refers to her as a chinese who betrayed her race as descendents of pigs. That means he acknowledges that some chinese are not. He must have thought that pig genes are not infused to some chinese so are more acceptable.

This misunderstanding is due to poor command of Malay. The Chinese do not mix with Malays, and only learn Malay in schools. In schools they are not taught how to insult others.

How about Melayu Mudah Lupa, a book, written by our Prime Minister, Dr. Mahathir Mohammad?

It is only a book title so grammar is not strict. The meaning defaults to a singular person. A Malay tends to forget easily. Or An Englishman Tends to Forget easily. It is never meant to condemn the entire race, although Dr. Mahathir's intention is to refer to the entire race, including himself. True to Dr. Mahathir's style, he does not use the correct grammatical form Orang Melayu Mudah Lupa, if he wants to refer to the entire race.

Does the author of the phrase "cina keturunan babi" intends to insult the entire race?
Maybe, but the grammar and usage of the words does not support it.
He probably exploited the chinese ignorance of the Malay phrase to maximise the insult on her.

And yet, the hypocritical chinese insults the Malays using the same phrases to the PM, Sultans of Malaysian States and the Bugis Race, as descendents of Pirates.

Similarly for the Jews. The Jews are the ones who complained of being subjected to racism and yet disallow Arab residents from returning to their homes or get citizenship, but allowing Jewish immigrants automatic citizenship, which is clearly racism, in all definitiions.