speech recognition

Pengenalan ucapan atau pengenalan wicara—dalam istilah bahasa Inggrisnya, automatic speech recognition (ASR)—adalah suatu pengembangan teknik dan sistem yang memungkinkankomputer untuk menerima masukan berupa kata yang diucapkan. Teknologi ini memungkinkan suatu perangkat untuk mengenali dan memahami kata-kata yang diucapkan dengan caradigitalisasi kata dan mencocokkan sinyal digital tersebut dengan suatu pola tertentu yang tersimpan dalam suatu perangkat. Kata-kata yang diucapkan diubah bentuknya menjadi sinyal digital dengan cara mengubah gelombang suara menjadi sekumpulan angka yang kemudian disesuaikan dengan kode-kode tertentu untuk mengidentifikasikan kata-kata tersebut. Hasil dari identifikasi kata yang diucapkan dapat ditampilkan dalam bentuk tulisan atau dapat dibaca oleh perangkat teknologi sebagai sebuah komando untuk melakukan suatu pekerjaan, misalnya penekanan tombol pada telepon genggam yang dilakukan secara otomatis dengan komando suara.

Alat pengenal ucapan, yang sering disebut dengan speech recognizer, membutuhkan sampel kata sebenarnya yang diucapkan dari pengguna. Sampel kata akan didigitalisasi, disimpan dalamkomputer, dan kemudian digunakan sebagai basis data dalam mencocokkan kata yang diucapkan selanjutnya. Sebagian besar alat pengenal ucapan sifatnya masih tergantung kepada pengeras suara. Alat ini hanya dapat mengenal kata yang diucapkan dari satu atau dua orang saja dan hanya bisa mengenal kata-kata terpisah, yaitu kata-kata yang dalam penyampaiannya terdapat jeda antar kata. Hanya sebagian kecil dari peralatan yang menggunakan teknologi ini yang sifatnya tidak tergantung pada pengeras suara. Alat ini sudah dapat mengenal kata yang diucapkan oleh banyak orang dan juga dapat mengenal kata-kata kontinu, atau kata-kata yang dalam penyampaiannya tidak terdapat jeda antar kata.

Sejak tahun 1940, perusahaan American Telephone and Telegraph Company (AT&T) sudah mulai mengembangkan suatu perangkat teknologi yang dapat mengidentifikasi kata yang diucapkan manusia. Sekitar tahun 1960-an, para peneliti dari perusahaan tersebut sudah berhasil membuat suatu perangkat yang dapat mengidentifikasi kata-kata terpisah dan pada tahun 1970-an mereka berhasil membuat perangkat yang dapat mengidentifikasi kata-kata kontinu. Alat pengenal ucapan kemudian menjadi sangat fungsional sejak tahun 1980-an dan masih dikembangkan dan terus ditingkatkan keefektifannya hingga sekarang.

Berdasarkan kemampuan dalam mengenal kata yang diucapkan, terdapat 5 jenis pengenalan kata, yaitu :

1.    Kata-kata yang terisolasi
Proses pengidentifikasian kata yang hanya dapat mengenal kata yang diucapkan jika kata tersebut memiliki jeda waktu pengucapan antar kata

2.    Kata-kata yang berhubungan
Proses pengidentifikasian kata yang mirip dengan kata-kata terisolasi, namun membutuhkan jeda waktu pengucapan antar kata yang lebih singkat

3.    Kata-kata yang berkelanjutan
Proses pengidentifikasian kata yang sudah lebih maju karena dapat mengenal kata-kata yang diucapkan secara berkesinambungan dengan jeda waktu yang sangat sedikit atau tanpa jeda waktu. Proses pengenalan suara ini sangat rumit karena membutuhkan metode khusus untuk membedakan kata-kata yang diucapkan tanpa jeda waktu. Pengguna perangkat ini dapat mengucapkan kata-kata secara natural

4.    Kata-kata spontan
Proses pengidentifikasian kata yang dapat mengenal kata-kata yang diucapkan secara spontan tanpa jeda waktu antar kata

5.    Verifikasi atau identifikasi suara
Proses pengidentifikasian kata yang tidak hanya mampu mengenal kata, namun juga mengidentifikasi siapa yang berbicara.

APLIKASI

Bidang komunikasi

Komando Suara
Komando Suara adalah suatu program pada komputer yang melakukan perintah berdasarkan komando suara dari pengguna. Contohnya pada aplikasi Microsoft Voice yang berbasis bahasa Inggris. Ketika pengguna mengatakan “Mulai kalkulator” dengan intonasi dan tata bahasa yang sesuai, komputer akan segera membuka aplikasi kalkulator. Jika komando suara yang diberikan sesuai dengan daftar perintah yang tersedia, aplikasi akan memastikan komando suara dengan menampilkan tulisan “Apakah Anda meminta saya untuk ‘mulai kalkulator’?”. Untuk melakukan verifikasi, pengguna cukup mengatakan “Lakukan” dan komputer akan langsung beroperasi.

Pendiktean
Pendiktean adalah sebuah proses mendikte yang sekarang ini banyak dimanfaatkan dalam pembuatan laporan atau penelitian. Contohnya pada aplikasi Microsoft Dictation yang merupakan aplikasi yang dapat menuliskan apa yang diucapkan oleh pengguna secara otomatis.

Telepon
Pada telepon, teknologi pengenal ucapan digunakan pada proses penekanan tombol otomatis yang dapat menelpon nomor tujuan dengan komando suara.

Bidang kesehatan

Alat pengenal ucapan banyak digunakan dalam bidang kesehatan untuk membantu para penyandang cacat dalam beraktivitas. Contohnya pada aplikasi Antarmuka Suara Pengguna atau Voice User Interface (VUI) yang menggunakan teknologi pengenal ucapan dimana pengendalian saklar lampu misalnya, tidak perlu dilakukan secara manual dengan menggerakkan saklar tetapi cukup dengan mengeluarkan perintah dalam bentuk ucapan sebagai saklarnya. Metode ini membantu manusia yang secara fisik tidak dapat menggerakkan saklar karena cacat pada tangan misalnya. Penerapan VUI ini tidak hanya untuk lampu saja tapi bisa juga untuk aplikasi-aplikasi kontrol yang lain.

Bidang militer

Pelatihan Penerbangan Aplikasi alat pengenal ucapan dalam bidang militer adalah pada pengatur lalu-lintas udara atau yang dikenal dengan Air Traffic Controllers (ATC) yang dipakai oleh para pilot untuk mendapatkan keterangan mengenai keadaan lalu-lintas udara seperti radar, cuaca, dan navigasi. Alat pengenal ucapan digunakan sebagai pengganti operator yang memberikan informasi kepada pilot dengan cara berdialog.

Helikopter
Aplikasi alat pengenal ucapan pada helikopter digunakan untuk berkomunikasi lewat radio dan menyesuaikan sistem navigasi. Alat ini sangat diperlukan pada helikopter karena ketika terbang, sangat banyak gangguan yang akan menyulitkan pilot bila harus berkomunikasi dan menyesuaikan navigasi dengan terlebih dahulu memencet tombol tertentu.

Tenses

Present Perfect Continuous Tense

I have been singing

How do we make the Present Perfect Continuous Tense?

The structure of the present perfect continuous tense is:

subject	+	auxiliary verb	+	auxiliary verb	+	main verb
		have has		been		base + ing

Here are some examples of the present perfect continuous tense:

	subject	auxiliary verb		auxiliary verb	main verb
+	I	have		been	waiting	for one hour.
+	You	have		been	talking	too much.
-	It	has	not	been	raining.
-	We	have	not	been	playing	football.
?	Have	you		been	seeing	her?
?	Have	they		been	doing	their homework?

Contractions

When we use the present perfect continuous tense in speaking, we often contract the subject and the first auxiliary. We also sometimes do this in informal writing.

I have been	I've been
You have been	You've been
He has been She has been It has been John has been The car has been	He's been She's been It's been John's been The car's been
We have been	We've been
They have been	They've been

Here are some examples:

·       I've been reading.

·       The car's been giving trouble.

·       We've been playing tennis for two hours.

How do we use the Present Perfect Continuous Tense?

This tense is called the present perfect continuous tense. There is usually a connection with the present or now. There are basically two uses for the present perfect continuous tense:

1. An action that has just stopped or recently stopped

We use the present perfect continuous tense to talk about an action that started in the past and stopped recently. There is usually a result now.

I'm tired because I've been running.
past		present			future
			!!!
Recent action.		Result now.

·       I'm tired [now] because I've been running.

·       Why is the grass wet [now]? Has it been raining?

·       You don't understand [now] because you haven't been listening.

2. An action continuing up to now

We use the present perfect continuous tense to talk about an action that started in the past and is continuing now. This is often used with for or since.

I have been reading for 2 hours.
past		present		future
Action started in past.		Action is continuing now.

·       I have been reading for 2 hours. [I am still reading now.]

·       We've been studying since 9 o'clock. [We're still studying now.]

·       How long have you been learning English? [You are still learning now.]

·       We have not been smoking. [And we are not smoking now.]

For and Since with Present Perfect Continuous Tense

We often use for and since with the present perfect tense.

·       We use for to talk about a period of time - 5 minutes, 2 weeks, 6 years.

·       We use since to talk about a point in past time - 9 o'clock, 1st January, Monday.

for	since
a period of time	a point in past time
		x
20 minutes	6.15pm
three days	Monday
6 months	January
4 years	1994
2 centuries	1800
a long time	I left school
ever	the beginning of time
etc	etc

Here are some examples:

·       I have been studying for 3 hours.

·       I have been watching TV since 7pm.

·       Tara hasn't been feeling well for 2 weeks.

·       Tara hasn't been visiting us since March.

·       He has been playing football for a long time.

·       He has been living in Bangkok since he left school.

Present Perfect Tense

I have sung

The present perfect tense is a rather important tense in English, but it gives speakers of some languages a difficult time. That is because it uses concepts or ideas that do not exist in those languages. In fact, the structure of the present perfect tense is very simple. The problems come with the use of the tense. In addition, there are some differences in usage between British and American English.

In this lesson we look at the structure and use of the present perfect, followed by a quiz to check your understanding:

·       Structure: how to make the present perfect tense

·       Use: when and why to use the present perfect tense

·       For and Since with the present perfect tense. What's the difference?

·       Present Perfect Quiz

Present Continuous Tense

I am singing

We often use the present continuous tense in English. It is very different from the simple present tense, both in structure and in use.

Simple Present Tense

I sing

How do we make the Simple Present Tense?

subject	+	auxiliary verb	+	main verb
		do		base

There are three important exceptions:

1.    For positive sentences, we do not normally use the auxiliary.

2.    For the 3rd person singular (he, she, it), we add s to the main verb or es to the auxiliary.

3.    For the verb to be, we do not use an auxiliary, even for questions and negatives.

Look at these examples with the main verb like:

	subject	auxiliary verb		main verb
+	I, you, we, they			like	coffee.
	He, she, it			likes	coffee.
-	I, you, we, they	do	not	like	coffee.
	He, she, it	does	not	like	coffee.
?	Do	I, you, we, they		like	coffee?
	Does	he, she, it		like	coffee?

Look at these examples with the main verb be. Notice that there is no auxiliary:

	subject	main verb
+	I	am		French.
	You, we, they	are		French.
	He, she, it	is		French.
-	I	am	not	old.
	You, we, they	are	not	old.
	He, she, it	is	not	old.
?	Am	I		late?
	Are	you, we, they		late?
	Is	he, she, it		late?

How do we use the Simple Present Tense?

We use the simple present tense when:

·       the action is general

·       the action happens all the time, or habitually, in the past, present and future

·       the action is not only happening now

·       the statement is always true

John drives a taxi.
past	present	future
It is John's job to drive a taxi. He does it every day. Past, present and future.

Look at these examples:

·       I live in New York.

·       The Moon goes round the Earth.

·       John drives a taxi.

·       He does not drive a bus.

·       We do not work at night.

·       Do you play football?

Note that with the verb to be, we can also use the simple present tense for situations that are not general. We can use the simple present tense to talk about now. Look at these examples of the verb "to be" in the simple present tense - some of them are general, some of them are now:

Am I right? Tara is not at home. You are happy.
past	present	future
The situation is now.

 

I am not fat. Why are you so beautiful? Ram is tall.
past	present	future
The situation is general. Past, present and future.

Past Perfect Continuous Tense

I had been singing

How do we make the Past Perfect Continuous Tense?

The structure of the past perfect continuous tense is:

subject	+	auxiliary verb HAVE	+	auxiliary verb BE	+	main verb
		conjugated in simple past tense		past participle		present participle
		had		been		base + ing

For negative sentences in the past perfect continuous tense, we insert not after the first auxiliary verb. For question sentences, we exchange the subject and first auxiliary verb. Look at these example sentences with the past perfect continuous tense:

	subject	auxiliary verb		auxiliary verb	main verb
+	I	had		been	working.
+	You	had		been	playing	tennis.
-	It	had	not	been	working	well.
-	We	had	not	been	expecting	her.
?	Had	you		been	drinking?
?	Had	they		been	waiting	long?

When speaking with the past perfect continuous tense, we often contract the subject and first auxiliary verb:

I had been	I'd been
you had been	you'd been
he had she had been it had been	he'd been she'd been it'd been
we had been	we'd been
they had been	they'd been

How do we use the Past Perfect Continuous Tense?

The past perfect continuous tense is like the past perfect tense, but it expresses longer actions in the past before another action in the past. For example:

·       Ram started waiting at 9am. I arrived at 11am. When I arrived, Ram had been waiting for two hours.

Ram had been waiting for two hours when I arrived.
past					present	future
Ram starts waiting in past at 9am.
	9		11
I arrive in past at 11am.

Here are some more examples:

·       John was very tired. He had been running.

·       I could smell cigarettes. Somebody had been smoking.

·       Suddenly, my car broke down. I was not surprised. It had not been running well for a long time.

·       Had the pilot been drinking before the crash?

You can sometimes think of the past perfect continuous tense like the present perfect continuous tense, but instead of the time being now the time is past.

past perfect continuous tense				present perfect continuous tense
had | been | doing | >>>> |	| | | |			| | | |	have | been | doing | >>>> |
past	now	future		past	now	future

For example, imagine that you meet Ram at 11am. Ram says to you:

·       "I am angry. I have been waiting for two hours."

Later, you tell your friends:

·       "Ram was angry. He had been waiting for two hours."

Past Perfect Tense

I had sung

The past perfect tense is quite an easy tense to understand and to use. This tense talks about the "past in the past".

Past Continuous Tense

I was singing

The past continuous tense is an important tense in English. We use it to say what we were in the middle of doing at a particular moment in the past.

Simple Past Tense

I sang

The simple past tense is sometimes called the preterite tense. We can use several tenses to talk about the past, but the simple past tense is the one we use most often.

Future Perfect Continuous Tense

I will have been singing

How do we make the Future Perfect Continuous Tense?

The structure of the future perfect continuous tense is:

subject	+	auxiliary verb WILL	+	auxiliary verb HAVE	+	auxiliary verb BE	+	main verb
		invariable		invariable		past participle		present participle
		will		have		been		base + ing

For negative sentences in the future perfect continuous tense, we insert not between will and have. For question sentences, we exchange the subject and will. Look at these example sentences with the future perfect continuous tense:

	subject	auxiliary verb		auxiliary verb	auxiliary verb	main verb
+	I	will		have	been	working	for four hours.
+	You	will		have	been	travelling	for two days.
-	She	will	not	have	been	using	the car.
-	We	will	not	have	been	waiting	long.
?	Will	you		have	been	playing	football?
?	Will	they		have	been	watching	TV?

When we use the future perfect continuous tense in speaking, we often contract the subject and auxiliary verb:

I will	I'll
you will	you'll
he will she will it will	he'll she'll it'll
we will	we'll
they will	they'll

For negative sentences in the future perfect continuous tense, we contract with won't, like this:

I will not	I won't
you will not	you won't
he will not she will not it will not	he won't she won't it won't
we will not	we won't
they will not	they won't

How do we use the Future Perfect Continuous Tense?

We use the future perfect continuous tense to talk about a long action before some point in the future. Look at these examples:

·       I will have been working here for ten years next week.

·       He will be tired when he arrives. He will have been travelling for 24 hours.

Future Perfect Tense

I will have sung

The future perfect tense is quite an easy tense to understand and use. The future perfect tense talks about the past in the future.

How do we make the Future Perfect Tense?

The structure of the future perfect tense is:

subject	+	auxiliary verb WILL	+	auxiliary verb HAVE	+	main verb
		invariable		invariable		past participle
		will		have		V3

Look at these example sentences in the future perfect tense:

	subject	auxiliary verb		auxiliary verb	main verb
+	I	will		have	finished	by 10am.
+	You	will		have	forgotten	me by then.
-	She	will	not	have	gone	to school.
-	We	will	not	have	left.
?	Will	you		have	arrived?
?	Will	they		have	received	it?

In speaking with the future perfect tense, we often contract the subject and will. Sometimes, we contract the subject, will and have all together:

I will have	I'll have	I'll've
you will have	you'll have	you'll've
he will have she will have it will have	he'll have she'll have it'll have	he'll've she'll've it'll've
we will have	we'll have	we'll've
they will have	they'll have	they'll've

 

We sometimes use shall instead of will, especially for I and we.

How do we use the Future Perfect Tense?

The future perfect tense expresses action in the future before another action in the future. This is the past in the future. For example:

·       The train will leave the station at 9am. You will arrive at the station at 9.15am. When you arrive, the train will have left.

The train will have left when you arrive.
past	present	future
		Train leaves in future at 9am.
			9		9.15
		You arrive in future at 9.15am.

Look at some more examples:

·       You can call me at work at 8am. I will have arrived at the office by 8.

·       They will be tired when they arrive. They will not have slept for a long time.

·       "Mary won't be at home when you arrive."
"Really? Where will she have gone?"

You can sometimes think of the future perfect tense like the present perfect tense, but instead of your viewpoint being in the present, it is in the future:

present perfect tense				future perfect tense
	| have | done | > |					will | have | done | > |

Future Continuous Tense

I will be singing

How do we make the Future Continuous Tense?

The structure of the future continuous tense is:

subject	+	auxiliary verb WILL	+	auxiliary verb BE	+	main verb
		invariable		invariable		present participle
		will		be		base + ing

For negative sentences in the future continuous tense, we insert not between will and be. For question sentences, we exchange the subject and will. Look at these example sentences with the future continuous tense:

	subject	auxiliary verb		auxiliary verb	main verb
+	I	will		be	working	at 10am.
+	You	will		be	lying	on a beach tomorrow.
-	She	will	not	be	using	the car.
-	We	will	not	be	having	dinner at home.
?	Will	you		be	playing	football?
?	Will	they		be	watching	TV?

When we use the future continuous tense in speaking, we often contract the subject and will:

I will	I'll
you will	you'll
he will she will it will	he'll she'll it'll
we will	we'll
they will	they'll

For spoken negative sentences in the future continuous tense, we contract with won't, like this:

I will not	I won't
you will not	you won't
he will not she will not it will not	he won't she won't it won't
we will not	we won't
they will not	they won't

 

We sometimes use shall instead of will, especially for I and we.

How do we use the Future Continuous Tense?

The future continuous tense expresses action at a particular moment in the future. The action will start before that moment but it will not have finished at that moment. For example, tomorrow I will start work at 2pm and stop work at 6pm:

At 4pm tomorrow, I will be working.
past	present	future
				4pm
		At 4pm, I will be in the middle of working.

When we use the future continuous tense, our listener usually knows or understands what time we are talking about. Look at these examples:

·       I will be playing tennis at 10am tomorrow.

·       They won't be watching TV at 9pm tonight.

·       What will you be doing at 10pm tonight?

·       What will you be doing when I arrive?

·       She will not be sleeping when you telephone her.

·       We 'll be having dinner when the film starts.

·       Take your umbrella. It will be raining when you return.

Simple Future Tense

I will sing

The simple future tense is often called will, because we make the simple future tense with the modal auxiliary will.

How do we make the Simple Future Tense?

The structure of the simple future tense is:

subject	+	auxiliary verb WILL	+	main verb
		invariable		base
		will		V1

For negative sentences in the simple future tense, we insert not between the auxiliary verb and main verb. For question sentences, we exchange the subject and auxiliary verb. Look at these example sentences with the simple future tense:

	subject	auxiliary verb		main verb
+	I	will		open	the door.
+	You	will		finish	before me.
-	She	will	not	be	at school tomorrow.
-	We	will	not	leave	yet.
?	Will	you		arrive	on time?
?	Will	they		want	dinner?

When we use the simple future tense in speaking, we often contract the subject and auxiliary verb:

I will	I'll
you will	you'll
he will she will it will	he'll she'll it'll
we will	we'll
they will	they'll

For negative sentences in the simple future tense, we contract with won't, like this:

I will not	I won't
you will not	you won't
he will not she will not it will not	he won't she won't it won't
we will not	we won't
they will not	they won't

How do we use the Simple Future Tense?

No Plan

We use the simple future tense when there is no plan or decision to do something before we speak. We make the decision spontaneously at the time of speaking. Look at these examples:

·       Hold on. I'll get a pen.

·       We will see what we can do to help you.

·       Maybe we'll stay in and watch television tonight.

In these examples, we had no firm plan before speaking. The decision is made at the time of speaking.

We often use the simple future tense with the verb to think before it:

·       I think I'll go to the gym tomorrow.

·       I think I will have a holiday next year.

·       I don't think I'll buy that car.

Prediction

We often use the simple future tense to make a prediction about the future. Again, there is no firm plan. We are saying what we think will happen. Here are some examples:

·       It will rain tomorrow.

·       People won't go to Jupiter before the 22nd century.

·       Who do you think will get the job?

Be

When the main verb is be, we can use the simple future tense even if we have a firm plan or decision before speaking. Examples:

·       I'll be in London tomorrow.

·       I'm going shopping. I won't be very long.

·       Will you be at work tomorrow?