Letter and sound recognition


The Alphabetic Principle | Reading Rockets

Not knowing letter names is related to children's difficulty in learning letter sounds and in recognizing words. Children cannot understand and apply the alphabetic principle (understanding that there are systematic and predictable relationships between written letters and spoken sounds) until they can recognize and name a number of letters.

Children whose alphabetic knowledge is not well developed when they start school need sensibly organized instruction that will help them identify, name, and write letters. Once children are able to identify and name letters with ease, they can begin to learn letter sounds and spellings.

Children appear to acquire alphabetic knowledge in a sequence that begins with letter names, then letter shapes, and finally letter sounds. Children learn letter names by singing songs such as the "Alphabet Song," and by reciting rhymes. They learn letter shapes as they play with blocks, plastic letters, and alphabetic books. Informal but planned instruction in which children have many opportunities to see, play with, and compare letters leads to efficient letter learning. This instruction should include activities in which children learn to identify, name, and write both upper case and lower case versions of each letter.

What is the "alphabetic principle"?

Children's reading development is dependent on their understanding of the alphabetic principle – the idea that letters and letter patterns represent the sounds of spoken language. Learning that there are predictable relationships between sounds and letters allows children to apply these relationships to both familiar and unfamiliar words, and to begin to read with fluency.

The goal of phonics instruction is to help children to learn and be able to use the Alphabetic Principle. The alphabetic principle is the understanding that there are systematic and predictable relationships between written letters and spoken sounds. Phonics instruction helps children learn the relationships between the letters of written language and the sounds of spoken language.

Two issues of importance in instruction in the alphabetic principle are the plan of instruction and the rate of instruction.

The alphabetic principle plan of instruction

  • Teach letter-sound relationships explicitly and in isolation.
  • Provide opportunities for children to practice letter-sound relationships in daily lessons.
  • Provide practice opportunities that include new sound-letter relationships, as well as cumulatively reviewing previously taught relationships.
  • Give children opportunities early and often to apply their expanding knowledge of sound-letter relationships to the reading of phonetically spelled words that are familiar in meaning.

Rate and sequence of instruction

No set rule governs how fast or how slow to introduce letter-sound relationships. One obvious and important factor to consider in determining the rate of introduction is the performance of the group of students with whom the instruction is to be used. Furthermore, there is no agreed upon order in which to introduce the letter-sound relationships. It is generally agreed, however, that the earliest relationships introduced should be those that enable children to begin reading words as soon as possible. That is, the relationships chosen should have high utility. For example, the spellings m, a, t, s, p, and h are high utility, but the spellings x as in box, gh, as in through, ey as in they, and a as in want are of lower utility.

It is also a good idea to begin instruction in sound-letter relationships by choosing consonants such as f, m, n, r, and s, whose sounds can be pronounced in isolation with the least distortion. Stop sounds at the beginning or middle of words are harder for children to blend than are continuous sounds.

Instruction should also separate the introduction of sounds for letters that are auditorily confusing, such as /b/ and /v/ or /i/ and /e/, or visually confusing, such as b and d or p and g.

Instruction might start by introducing two or more single consonants and one or two short vowel sounds. It can then add more single consonants and more short vowel sounds, with perhaps one long vowel sound. It might next add consonant blends, followed by digraphs (for example, th, sh, ch), which permits children to read common words such as this, she, and chair. Introducing single consonants and consonant blends or clusters should be introduced in separate lessons to avoid confusion.

The point is that the order of introduction should be logical and consistent with the rate at which children can learn. Furthermore, the sound-letter relationships chosen for early introduction should permit children to work with words as soon as possible.

Many teachers use a combination of instructional methods rather than just one. Research suggests that explicit, teacher-directed instruction is more effective in teaching the alphabetic principle than is less-explicit and less-direct instruction.

Guidelines for rate and sequence of instruction

  • Recognize that children learn sound-letter relationships at different rates.
  • Introduce sound-letter relationships at a reasonable pace, in a range from two to four letter-sound relationships a week.
  • Teach high-utility letter-sound relationships early.
  • Introduce consonants and vowels in a sequence that permits the children to read words quickly.
  • Avoid the simultaneous introduction of auditorily or visually similar sounds and letters.
  • Introduce single consonant sounds and consonant blends/clusters in separate lessons.
  • Provide blending instruction with words that contain the letter-sound relationships that children have learned.

50 ABC Letters and Sounds Games • Kids Activities Blog

Today we have a whole bunch of alphabet fun with letter and sounds learning games and activities for toddlers and preschoolers to help you young students prepare to read with fun pre-reading playful learning ideas.

ABC Games & Alphabet Sounds

Many parents have kids that are soon to enter kindergarten for the first time and are wondering what their kids should know before they head out to school on their own.

As a mom who once taught Kindergarten, I always wanted to make sure my kids are well-prepared and ready to begin their school career with a bit of an advantage by knowing their letters and sounds.

Related: Grab our free Kindergarten readiness checklist as a guide

I have seen the value in children knowing their letters early.

That said, I also recognize that kids are kids, and I want to make sure they have time to play – both independently and with me.

Let’s learn our alphabet through playing games!

Learning Through Alphabet Games

Children acquire knowledge through play, so learning letters at our house is rarely a sit down structured time.

It’s a time of play and games!

The kids have fun and don’t even realize they are learning at the same time. I don’t believe we should leave teaching up to the schools. You get the great honor of being an educator of your child, and you can supplement what is happening at school by engaging your child in enjoyable yet educational ways.

Related: Check out our huge abc letters resource that has letter activities, letter crafts, letter printables and more for every letter of the alphabet!

I hope these resources help you feel equipped to take the reins in your own child’s education.  

This article contains affiliate links.

Let’s play a hands on letter game!

Hands On Letter Games

1. Letter Toss Game

Muffin Tin Learning  – Want to make learning fun? This game involving throwing pennies and will keep your kids engaged. They will  barely know that this is actually a lesson.

2. Growing Letters Game

Alphabet Flower Garden –  This garden is full of letters and learning opportunities. It is definitely a great way to explore and grow in alphabet knowledge.

3. Unlimited ABC Games for Kids

ABC Mouse – This site gives kids tons of alphabet and phonics practice through interactive games and printables.

4. Matching Letter Game

Magnetic Alphabet Board – This letter matching activity is self-contained and is a tool to get  kids to match up letters and help with identification.

5. Touch and Feel the Alphabet Game

Play Dough and Magnet Letters – Letting kids explore using their senses is a great way to learn. Play Dough is a tactile  way to watch this happen.

–>Need a Set of Alphabet Magnets? I like this Magnetic Letters Alphabet Fridge Magnets Set that comes in a handy carrying tub.

6. The Great Alphabet Race

Race the Alphabet – Do you have race tracks and a child that loves playing with cars? This activity is for you! If you don’t have your own track, here’s another version.

Let’s have some fun with preschool learning games & our ABC’s.

Preschool Alphabet Games

7.

Fishing for Letters

Magnet Letter Fishing  – Take your magnet letters and make a simple fishing pole. With a pond full of letters, your kids will have a lot of fun  casting their line for another catch.

8. Pirate Vowel Game

Gold Coin Vowel Sound Drop – Your little pirate will have fun learning his or her vowels be playing this game.

9. Letter Stacking Game

ABC Letter Stack Game – Stacking up letters has never been so fun. They get to stack and stack until they fall, which I am sure will become the favorite part.

Related: Use these with our playful preschool homeschool curriculum

10. It Begins With…

Initial Sounds Blackout Game  – Want kids to be able to identify the beginning sounds of words? This fun game will help them do exactly that.

–>Need a Wooden Alphabet Set with Flashcards? I really love the cuteness of this Tangame Wooden Magnetic Letters Alphabet Refrigerator Magnet Flash Cards for Preschool Kids that comes in a magnetic tin.

11. Letter Scavenger Hunt

Architecture Letter Scavenger Hunt – Have you seen those photos that find letters in architecture? Your kids get to go on their own letter scavenger hunt with this fun activity.

Let’s play a creative alphabet game!

Creative Letter Games for Alphabet Sounds

12. Interactive Alphabet Learning Games

A-Z Letter Learning Activities – This post brings you over 90 activities for each and every letter of the alphabet. What a great resource!

13. Climb the Word Ladder

Word Ladder – Kids get to “climb” to the top of the ladder as they successfully identify letters and sounds. They don’t need to worry if they “fall,” they have the opportunity to try again.

14. Flashlight Alphabet Game

Flashlight Alphabet Game – My kids are obsessed with flashlights. I know my preschooler would love this game!

–>Need Foam Alphabet Letters for Practice? This Gamenote Classroom Magnetic Alphabet Letters Kit comes in a plastic organization case and magnet board and would be great for home too.

15. Make a Letter Game

Letter Formation Activity – Using materials you probably have at home, your kids will have a lot of fun forming their letters.

16. Hungry Hungry Letters Game

Alphabet Monster  – This hungry monster will only eat letters if you can say the name or sound of a letter. What a fun craft to make that also turns a great letter learning opportunity.

Let’s play a game that helps us learn letters!

ABC Games that Help Kids Learn Letters and Sounds

17. Let’s Host a Reading Hop

Reading Hop  – This letter learning game will keep your kids active and hopping all around. If you are looking for a way to take learning outdoors, you have found it.

18. Alphabet I Spy

Alphabet “I Spy” – Take the classic and beloved game of “I Spy” and turn it into an alphabet search activity. Brilliant!

19. Can You Catch the Letters Game?

Runaway Letters Game  – Your child gets a chance to grab letters and runaway while you creativity beacon the letter’s return. This is a great way for moms, dads or teachers to interact with their kids during the educational process.

–>Need a Fun ABC Game? I love this ABC Cookies Game from Goodie Games that is a fun alphabet learning game for toddlers and preschoolers.

20. LEGO Spelling

Lego Spelling  – If you add letters to duplex legos, you have a great way to work on sounds and words.

21. Letters Inside of Letters Activity

Making Letters with Letters – Learning letters will be reinforced over and over again as your kids use letters from magazines to create their own larger letters.

Fun Pre-K Learning games for kids!

ABC Games for Pre-K

22. Letter Swat Game

Spider Letter Swat – Kids will enjoy learning their letters as they swat away at the flies in this entertaining game.

23. Letter Squirt Game

Squirt the Letter  – This is a game I know my son, especially, would love. He loves anything squirt gun and anything water. Squirting the correct letter is right up his alley.

24. Letter Lacing Activity

Letter Lacing – This letter lacing, quiet bag activity works on fine motor skills while also developing the skills needed to develop in reading.

–>Need Letter Lacing Cards? I like this wooden set from Melissa & Doug that has both animals and letters on the sturdy lacing cards.

25. Alphabet Sounds Race

Letter Sounds Race – Get your kids moving with this letter sounds race. This is a great learning opportunity for your active kids! More alphabet sound learning activities are fun too!

26. Disappearing Letters Game

Disappearing Letters  – Kids will learn to love to trace their letters as they see  the trick to making them disappear.

Let’s play ABC Learning Games!

Alphabet Games for Learning

27. The Game of Bang

Bang – Bang is a letter identification game that will be a lot of fun for the little gamers in your life.

28. Letter Chomp Game

Mr. Shark Alphabet Chomper Game  – I love the idea to make a shark out of an envelope in general. Add the learning aspect of having the shark chomp letters, and you have a great game.

29. Letter Tiles Activity

DIY Bananagrams Letter Tiles – Here’s a really smart way to make letter tiles. You can turn them into magnets or play the classic Bananagram game with your creation.

–>Need a Bananagram Game? Here is the original Bananagram game for kids.

30. Make Pretzel Letters

Soft Pretzel Letters – Kids can learn their letters as they have fun making pretzel dough. Through using both the sense of touch and taste, this becomes a fun activity for all.

31. Travel Alphabet Game

Alphabet Words Game – This is a learning game that can be taken anywhere. Keep your kids occupied working on their letters at restaurants, home, car rides and more.

Let’s play letter and sound games!

ABC Games for Letters and Sounds

32.

Touchy Feely Letters

Sensory Bins with Letters – Sometimes the best way to help kids learn is to let them explore. This sensory bin will help kids do just that.

33. Alphabet Seek & Find

Seek-N-Find Alphabet – This letter game is like an eye spy for letters. It involves a plastic tube (easily substituted by a water bottle), and will keep your kids searching for their letters for quite some time.

34. Letter Formation Fun

Tactile Writing – Kids learn to write letters as they use rice and paint  to feel their way through the process or writing.

–>Need a Wooden Letter Matching Set? I like this durable Alphabet flash cards and wooden letter puzzle set from LiKee Alphabet.

35. Homemade Domino Letter Fun

Craft Stick Dominos  – These craft stick dominos are an easy, homemade version of a domino game with a  focus on learning letters and matching symbols. What a fun idea.

36. Flashcard Games

ABC Flashcards  – Flashcards can be used by a variety of games and activities like flashcard basketball. These ones are free. And so are these kids alphabet cards you can download & print instantly.

Related: Here are a bunch of ideas for flash card games for kids

Let’s play some more abc games!

How to Help a Child Learn Letters and Sounds Through Play

37. Make a Sun-Powered Letter Puzzle

Make a DIY shape puzzle using the sun with alphabet letters for a really fun matching game you can play inside or out. Or use this method without the sun to make this fun abc matching game for kids.

38. Collect Alphabet Treasures

Use these free alphabet labels to create small containers for each letter of the alphabet for a special letter collection activity!

39. Make Easy Alphabet Crackers

Making alphabet crackers has never been easier or more fun!

–>Need an Alphabet Snack? I like these Happy Tot Organics ABC Multi-Grain Cookies…yum!

40. Play Alphabet Zipline!

Use these alphabet printable letters to create your own alphabet zipline in your living room. It is really fun.

41. Play a Silly Letters Game

Try these alphabet games for preschool that are full of fun and a little silly…

42. Make Pipecleaner Letters!

Try to do some fun abc formation with pasta and pipe cleaners which is a fun way to explore letter shapes.

43. Make Bathtub Alphabet Soup

Use bath letters for a big big big batch of bubblebath alphabet soup {giggle}.

44. Color a Letter Coloring Page

  • Letter A Coloring Page
  • Letter B Coloring Page
  • Letter C Coloring Page
  • Letter D Coloring Page
  • Letter E Coloring Page
  • Letter F Coloring Page
  • Letter G Coloring Page
  • Letter H Coloring Page
  • Letter I Coloring Page
  • Letter J Coloring Page
  • Letter K Coloring Page
  • Letter L Coloring Page
  • Letter M Coloring Page
  • Letter N Coloring Page
  • Letter O Coloring Page
  • Letter P Coloring Page
  • Letter Q Coloring Page
  • Letter R Coloring Page
  • Letter S Coloring Page
  • Letter T Coloring Page
  • Letter U Coloring Page
  • Letter V Coloring Page
  • Letter W Coloring Page
  • Letter X Coloring Page
  • Letter Y Coloring Page
  • Letter Z Coloring Page

45.

Let’s Play with Playdough!

These playdough pre writing activities are both fun and super hands-on learning.

Let’s make a yummy…I mean gummy…alphabet!

46. Make Gummy Letters

This sour gummy recipe makes the cutest alphabet letters to learn and eat!

47. Try a Fun Alphabet Activity Book

There are so many quality workbooks for kids on the market right now so we narrowed it down to some of our favorites that just might fit your kid.

Let’s find the letters and make pictures with crayons!

48. Color by Letter Activities for Letter Recognition Fun

We have a whole bunch of color by letter printable pages for kids that help them recognize letters while playing a game:

  1. Color by letter – A-E
  2. Color by letter worksheets – F-J
  3. Coloring by letters – K-O
  4. Color with letters – P-T
  5. Preschool color by letter – U-Z

49. Play the Missing Letter Game

Use one of our favorite preschool games, What is Missing? and use either letter flashcards or abc fridge magnet sets to create sequencing of the alphabet and then remove a letter or two.

Let’s have fun with letter recognition!

50. Play Alphabet Beach Ball Toss

Modify our fun sight word game with letters instead of sight words. Your beach ball can be covered with the letters of the alphabet for throwing and catching learning fun.

Games for ABC Sounds

51. Learn and sing the ABC sounds song

I love this fun song from Rock ‘N Learn that goes through the entire alphabet with sounds for each of the letters.

52. Play an online ABC sounds game

Monster Mansion is a free online alphabet match game that kids can learn the abc sounds and match them with the proper letter on the proper monster!

53. Print & Play a letter sounds game

Preschool Play and Learn has a really colorful and fun letter sounds board game you can print and play at home or in the preschool classroom. Each player will pick up a card and identify the letter and /or say the sound that the letter makes.

More Learning Games from Kids Activities Blog

  • Now that we learned out letters, don’t miss out on our number activities for preschoolers!
  • When your child is ready, we have a big giant list of sight word activities that are fun too!
  • We have some really fun games teaching kids how to read a clock.
  • My favorite massive resource of fun is our kids science games here at Kids Activities Blog.
  • It doesn’t have to be October to play some frightful Halloween games.
  • Let’s play math games for kids!
  • If you need to work out the wiggles, we have the best indoor games for kids.

What was your favorite abc game? Did we miss some alphabet activities that you do with your kids?

Recognition of vowels, consonants and letters

Sections: Primary school


Objectives:

  • to develop the ability to recognize vowels and consonants by their essential features;
  • develop the ability to observe the pronunciation of speech, conduct their sound analysis; develop a love for nature.

Lesson progress

I. Org. Moment

Music is playing. "Voices of Birds".

- What do we hear? (voices, sounds)

- What is written on the blackboard? (sentence, letters)

II. Lesson topic message

On the board: Recognition of vowels and consonants and letters.

- Queens of Voice and Concord and their assistants - sounds are present at the lesson.

Glasa and her assistant (percussive sound).

Queen Consent and her assistants (voiced soft, voiced hard, voiceless hard, voiceless soft)

III. Calligraphic letter

A strong wind blew and the flower bent. Why?

We write AND in uppercase and and in lowercase.

IV . Observation of consonants and vowels and letters

Thread Gossamer brought us in an envelope - what?

(y, a, i, s, l, k)

(Letters - y, a, i, s, l, k)

- What groups can they be divided into? (vowels, consonants)

- Name the sounds, ([u], [a], [i], [s], [l], [k])

Poems about sounds (learned by students)

  1. Vowels stretch in a ringing song,
    Can cry and scream,
    They can cradle the baby in the crib,
    But they do not regret whistling and grumbling.
  2. A consonants agree
    Rustle, whisper, creak,
    Even snort and hiss,
    But they don't want to sing.
  3. A lot of trouble with letters,
    They are such a people . ..
    But when it's smart
    Build them in a clear row -
    Letters will turn into a word
    And they will talk to you!

- Let's make words from these letters and write them down.

(fox, bow, varnish, power)

- There is something else in the envelope! (frogs)

V . Fizminutka

Two girlfriends, two green frogs
Washed early in the morning,
Rubbed with a towel.
Paws stomped,
paws clapped,
Right, left leaned
And they returned back.

VI . Continuation of work on the topic of the lesson

A) Filling in the crossword puzzle.

- What is in the pictures?

How to call in one word? (trees)

What kind of trees are these? Name and show.

B) Work in a notebook.

- Let's write down the names of trees in a notebook: oak, aspen, pine, birch.

- How many letters and sounds are in each word?

- How should trees be protected? What needs to be done for this?

C) Reward for a difficult task:

Who will correctly name - how many letters and how many sounds in the word TREES ?

The result of the lesson

- What did you do at the lesson?

- Which task did you like the most? Why?

Let the trees grow, flowers bloom,
And we listen to the birds singing!

Machine learning is fun! Part 6: Speech recognition with deep learning | by Pavel Pleskov

Translation of a series of articles ADAM GEITGEY - “Machine Learning is fun!”: p. 1 , .5 , h.6 , h.7 , h.

Speech recognition is invading our lives. It is already in phones, game consoles and even smart watches. Even our homes are being automated with speech. For just $50, you can buy an Amazon Echo Dot, a magical box that lets you order a pizza, get a weather forecast, or even buy trash bags—just say the command:

The Echo Dot has been so popular this holiday season that Amazon can't keep up with them!

But speech recognition has been around for decades, so why is it just now becoming mainstream? The reason is that deep learning has finally made speech recognition accurate enough to be useful outside of a carefully controlled environment.

Andrew Ng predicted long ago that since speech recognition already works with 95-99% accuracy, it will soon become the main way we interact with computers. But the fact is that it is these 4% that determine the difference between an “irritatingly unreliable” and an “incredibly useful” algorithm. Thanks to deep learning, we have finally reached the top.

Let's learn how to recognize speech using deep learning!

If you know how neural network machine translation works, you can guess that you can simply feed sound recordings to a neural network and train it on them: when I wrote this, I thought that we would come to this in a couple of years).

A serious problem is that speech has an inconsistent rate. One person can say "hello!" very quickly, and the other will say “rrrrrriiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiinginginging!” very slowly, creating a much longer sound file with much more data. Meanwhile, both sound files should be recognized as the same text - "hello!". Automatically aligning audio files of varying lengths to a fixed-length piece of text is not an easy task.

To get around this problem, we'll have to use some special tricks and extra precision in addition to the deep neural network. Let's see how it works!

The first step in speech recognition is obvious - we need to transfer the sounds to the computer.

In the third part, we learned how to take an image and represent it as an array of numbers to directly connect to the neural network for image recognition:

But sound is waves . How to turn sound waves into numbers? Let's use the following audio file with the text "hello":

Sound waves are one-dimensional. At each point in time they have one value, depending on the amplitude of the wave. Let's zoom in on some small part of the sound wave and take a closer look:

To turn this sound wave into numbers, we simply write the amplitude values ​​of the wave at equidistant points:

This is called sampling . We read data thousands of times per second and write down the numbers corresponding to the amplitude of the sound wave at that moment in time. Uncompressed .wav audio files are obtained.

Audio recorded on CDs is sampled at 44.1 kHz (44,100 samples per second). But for speech recognition, a sampling rate of 16 kHz (16,000 samples per second) is sufficient, since the frequency range of human speech is not so large.

Let's digitize our Hello 16000 times per second. Here are the first 100 points:

You might think that sampling only creates an approximate version of the original sound wave, because we take random readings, and data is lost in between samples, right?

But thanks to Kotelnikov's theorem, we know that in order to perfectly recreate the original sound wave, it is enough to use a sampling frequency twice the highest frequency of the recorded sound.

I'm only dwelling on this because almost everyone mistakenly thinks that using higher sample rates always results in better sound quality. This is not true.

We now have an array of numbers, each representing the amplitude of the sound wave at 1/16000 second intervals.

We could simply train the neural network on these numbers, but recognizing speech patterns by processing these numbers directly is difficult. Instead, we can make things easier by doing some pre-processing on the audio data.

Let's start by grouping our samples into chunks of 20 milliseconds. Here is the first such fragment (the first 320 samples):

Plotting these numbers as a simple line graph gives an approximate image of the original sound wave over the selected 20 millisecond time period:

This entry is only 1/50 of a second long . But even it is a complex mixture of different frequencies of sound. There are some low sounds, there are mid-range sounds and even some high sounds. All these frequencies are mixed together - and the result is the sound of human speech.

To simplify the processing of this data for the neural network, we decompose a complex sound wave into its component parts, starting from the lowest frequencies. Then, by summing the sound powers in each frequency band, we create a frequency picture sound.

Imagine that you had a recording of someone playing the chord in C major on the piano. This sound is a combination of three musical notes - Do , Mi and Sol - which are mixed into one complex sound. We want to break this complex sound into individual notes in order to discover the original notes. Here is the same.

This is done using a mathematical operation called the Fourier transform. We decompose a complex sound wave into the simple sound waves that make it up. Having separate sound waves, we add up the sound powers in each of them.

The end result is an evaluation of the importance of each frequency range, from low frequencies to high frequencies. The numbers below show the audio power in each 50 Hz band in our original sample:

Much easier and clearer to understand this if we draw a diagram:

If we repeat this process on every 20-millisecond audio fragment, we get a spectrogram (each column from left to right is one 20-millisecond chunk):

The spectrogram is cool because it can highlight musical notes and other tones in audio data. It will be easier for a neural network to find patterns in such data than in raw sound recordings. Now we have received the data that we will transfer to our neural network.

Now that we have an audio format that we can work with, we will train a deep neural network on this data. The neural network will receive audio fragments with a length of 20 ms. For each small fragment, the network will try to determine which letter was spoken.

We will use a recurrent neural network, that is, one that takes into account the results of previous steps at each step. We do this because each letter determined by the network must influence the likely next letter. For example, if we said "HI", then most likely, we will say "ET" next to complete the word "Hi". It is much less likely that we will say something unpronounceable, such as "Shhh". Thus, by remembering previous results, the neural network will be able to make more accurate predictions in the future.

After we run our entire audio file through the neural network (one fragment at a time), we get the decomposition of each audio fragment into the letters most likely spoken during this fragment. Here's what the "Hi" display looks like:

Our neural network is predicting that I'll say "HOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOAY". But she might also think that I said "HOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO down

We have to put the results in order in several steps. First, we will replace any duplicate characters with a single character: unpronounceable transcriptions. For example, if you say "He won't go", the network might return "One pay dyod".

The trick is to refine these predictions by comparing them to a large database of written text (books, news articles, etc.). We discard the transcriptions that seem the least likely and choose the one that seems the most realistic.

Of our transcriptions for "Hello", "Preved", and "Priuet", apparently "Hello" occurs more frequently in the text database (not to mention our original audio files), and so is probably the correct one. Therefore, we will choose "Hello" as our final transcription. Ready!

You might be thinking: “ But what if someone says “ Preved ”? That would be the correct word, and "Hello" would be the wrong transcription of !"

Of course, it is possible that someone will actually say “Hello” instead of “Hi”. But a speech recognition system like this (trained in standard language) won't pick Preved as the correct choice. Also, when you say "Hello" you still mean "Hi" even if you underline the E and D.

Try this - if your phone is set to recognize the language, try saying "Preved" to the phone. He will refuse to understand you, and will inexorably recognize this as "Hi."

Non-recognition of "Preved" is normal, but it may also be that your phone simply refuses to understand something really correct and important. That is why these speech recognition models are always trained on a large amount of data to correct errors.

One of the coolest things about machine learning is that it seems to be very simple. You get a bunch of data, feed it into a machine learning algorithm, and then magically you have a world-class AI system that runs on your laptop... yes ?

Yes, sometimes it works, but not for speech. Speech recognition is a complex task. You have to overcome a hundred different difficulties: poor microphone quality, background noise, reverb and echo, pronunciation and accent variations, and much more. All of these issues need to be accounted for in the training data to make sure the neural network can handle them.

Here is another example. Did you know that when you speak in a noisy room, you subconsciously speak in a higher tone to shout over the noise? People understand you without problems, but teaching this to a neural network is a whole task. So your training data should have people screaming in the noise!

To build a voice recognition system that works like Siri, Google Now, or Alexa, you'll need lots of training data—much more data than you can probably get without hiring hundreds of people to record it. Meanwhile, you can’t save on this - no one wants a voice recognition system that works only 80% of the time.

Google and Amazon use hundreds of thousands of hours of spoken language recorded in real situations. This is the biggest point that separates a world-class speech recognition system from your hobby. The point is that Google Now and Siri that work for free, or $50 magic boxes Alexa that don't have a subscription fee, are designed to get you to use them as much as possible . Whatever you say to them, then is recorded forever as and will be used as training data for future versions of speech recognition algorithms. That's where the focus is!

Don't believe me? If you have an Android phone with Google Now , click here to listen to all the stupid things you've ever said:

So if you're looking for a startup idea, I wouldn't recommend building your own speech recognition system and competing with Google.


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