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5706315b52bb891400689950
Which standard does not include a specification for an MP3 encoder?
MPEG-1
[ "MP3\n\nThe MPEG-1 standard does not include a precise specification for an MP3 encoder, but does provide example psychoacoustic models, rate loop, and the like in the non-normative part of the original standard. At present, these suggested implementations are quite dated. Implementers of the standard were supposed...
5706315b52bb891400689951
Example psychoacoustic models and rate loops can be foundin which part of the original standard?
non-normative
[ "MP3\n\nThe MPEG-1 standard does not include a precise specification for an MP3 encoder, but does provide example psychoacoustic models, rate loop, and the like in the non-normative part of the original standard. At present, these suggested implementations are quite dated. Implementers of the standard were supposed...
5706315b52bb891400689952
What were implementers of the standard supposed to devise?
their own algorithms
[ "MP3\n\nThe MPEG-1 standard does not include a precise specification for an MP3 encoder, but does provide example psychoacoustic models, rate loop, and the like in the non-normative part of the original standard. At present, these suggested implementations are quite dated. Implementers of the standard were supposed...
5706315b52bb891400689953
It is easy for a prospective user of an encoder to research the best choice because of what factor?
Comparisons are widely available
[ "MP3\n\nThe MPEG-1 standard does not include a precise specification for an MP3 encoder, but does provide example psychoacoustic models, rate loop, and the like in the non-normative part of the original standard. At present, these suggested implementations are quite dated. Implementers of the standard were supposed...
5706315b52bb891400689954
An encoder that is proficient at encoding at higher bit rates might be worse at what?
lower bit rates
[ "MP3\n\nThe MPEG-1 standard does not include a precise specification for an MP3 encoder, but does provide example psychoacoustic models, rate loop, and the like in the non-normative part of the original standard. At present, these suggested implementations are quite dated. Implementers of the standard were supposed...
5706324275f01819005e7a6a
How many domain samples are taken during encoding?
576
[ "MP3\n\nDuring encoding, 576 time-domain samples are taken and are transformed to 576 frequency-domain samples.[clarification needed] If there is a transient, 192 samples are taken instead of 576. This is done to limit the temporal spread of quantization noise accompanying the transient. (See psychoacoustics.)" ]
5706324275f01819005e7a6b
Domain samples are transformed into what?
frequency-domain samples
[ "MP3\n\nDuring encoding, 576 time-domain samples are taken and are transformed to 576 frequency-domain samples.[clarification needed] If there is a transient, 192 samples are taken instead of 576. This is done to limit the temporal spread of quantization noise accompanying the transient. (See psychoacoustics.)" ]
5706324275f01819005e7a6c
When are 192 samples taken instead of 576?
there is a transient
[ "MP3\n\nDuring encoding, 576 time-domain samples are taken and are transformed to 576 frequency-domain samples.[clarification needed] If there is a transient, 192 samples are taken instead of 576. This is done to limit the temporal spread of quantization noise accompanying the transient. (See psychoacoustics.)" ]
5706324275f01819005e7a6d
When 192 samples are taken instead of 576, it is done in an effort to limit what?
temporal spread
[ "MP3\n\nDuring encoding, 576 time-domain samples are taken and are transformed to 576 frequency-domain samples.[clarification needed] If there is a transient, 192 samples are taken instead of 576. This is done to limit the temporal spread of quantization noise accompanying the transient. (See psychoacoustics.)" ]
5706324275f01819005e7a6e
What accompanies a transient?
quantization noise
[ "MP3\n\nDuring encoding, 576 time-domain samples are taken and are transformed to 576 frequency-domain samples.[clarification needed] If there is a transient, 192 samples are taken instead of 576. This is done to limit the temporal spread of quantization noise accompanying the transient. (See psychoacoustics.)" ]
5706336875f01819005e7a86
What kind of structure does a filter bank have?
tree
[ "MP3\n\nDue to the tree structure of the filter bank, pre-echo problems are made worse, as the combined impulse response of the two filter banks does not, and cannot, provide an optimum solution in time/frequency resolution. Additionally, the combining of the two filter banks' outputs creates aliasing problems that...
5706336875f01819005e7a87
Due to a specific kind of structure, what kind of problems are made worse?
pre-echo problems
[ "MP3\n\nDue to the tree structure of the filter bank, pre-echo problems are made worse, as the combined impulse response of the two filter banks does not, and cannot, provide an optimum solution in time/frequency resolution. Additionally, the combining of the two filter banks' outputs creates aliasing problems that...
5706336875f01819005e7a88
What kind of resolution are the filter banks unable to provide an optimal solution for?
time/frequency
[ "MP3\n\nDue to the tree structure of the filter bank, pre-echo problems are made worse, as the combined impulse response of the two filter banks does not, and cannot, provide an optimum solution in time/frequency resolution. Additionally, the combining of the two filter banks' outputs creates aliasing problems that...
5706336875f01819005e7a89
Combining two filter banks' outputs creates what kind of problem?
aliasing
[ "MP3\n\nDue to the tree structure of the filter bank, pre-echo problems are made worse, as the combined impulse response of the two filter banks does not, and cannot, provide an optimum solution in time/frequency resolution. Additionally, the combining of the two filter banks' outputs creates aliasing problems that...
5706336875f01819005e7a8a
The need to code excess energy in the frequency domain decreases what kind of efficiency?
coding
[ "MP3\n\nDue to the tree structure of the filter bank, pre-echo problems are made worse, as the combined impulse response of the two filter banks does not, and cannot, provide an optimum solution in time/frequency resolution. Additionally, the combining of the two filter banks' outputs creates aliasing problems that...
5706347875f01819005e7a90
What is carefully defined in the standard?
Decoding
[ "MP3\n\nDecoding, on the other hand, is carefully defined in the standard. Most decoders are \"bitstream compliant\", which means that the decompressed output that they produce from a given MP3 file will be the same, within a specified degree of rounding tolerance, as the output specified mathematically in the ISO/...
5706347875f01819005e7a91
What are most decoders?
bitstream compliant
[ "MP3\n\nDecoding, on the other hand, is carefully defined in the standard. Most decoders are \"bitstream compliant\", which means that the decompressed output that they produce from a given MP3 file will be the same, within a specified degree of rounding tolerance, as the output specified mathematically in the ISO/...
5706347875f01819005e7a92
The ISO/IEC high standard document states that the decompressed output produced from a given MP3 file will be the same within what standards?
specified degree of rounding tolerance
[ "MP3\n\nDecoding, on the other hand, is carefully defined in the standard. Most decoders are \"bitstream compliant\", which means that the decompressed output that they produce from a given MP3 file will be the same, within a specified degree of rounding tolerance, as the output specified mathematically in the ISO/...
5706347875f01819005e7a93
Decoders are usually compared by examining which factor?
computationally efficient
[ "MP3\n\nDecoding, on the other hand, is carefully defined in the standard. Most decoders are \"bitstream compliant\", which means that the decompressed output that they produce from a given MP3 file will be the same, within a specified degree of rounding tolerance, as the output specified mathematically in the ISO/...
5706347875f01819005e7a94
The efficiency of decoders is examined by seeing how much memory and what other process they use in the decoding process?
CPU time
[ "MP3\n\nDecoding, on the other hand, is carefully defined in the standard. Most decoders are \"bitstream compliant\", which means that the decompressed output that they produce from a given MP3 file will be the same, within a specified degree of rounding tolerance, as the output specified mathematically in the ISO/...
570634ea75f01819005e7a9a
What is there no official provision for?
gapless playback
[ "MP3\n\nEncoder / decoder overall delay is not defined, which means there is no official provision for gapless playback. However, some encoders such as LAME can attach additional metadata that will allow players that can handle it to deliver seamless playback." ]
570634ea75f01819005e7a9b
What is an example of an encoder that can attach additional metadeta?
LAME
[ "MP3\n\nEncoder / decoder overall delay is not defined, which means there is no official provision for gapless playback. However, some encoders such as LAME can attach additional metadata that will allow players that can handle it to deliver seamless playback." ]
570634ea75f01819005e7a9c
Adding additional metadata allows players to handle gapless playback and deliver what?
seamless playback
[ "MP3\n\nEncoder / decoder overall delay is not defined, which means there is no official provision for gapless playback. However, some encoders such as LAME can attach additional metadata that will allow players that can handle it to deliver seamless playback." ]
570634ea75f01819005e7a9d
For encoders and decoders, what is not defined?
overall delay
[ "MP3\n\nEncoder / decoder overall delay is not defined, which means there is no official provision for gapless playback. However, some encoders such as LAME can attach additional metadata that will allow players that can handle it to deliver seamless playback." ]
5706371452bb89140068996e
A typical trade off when creating an MP3 file is between the amount of space used and what other factor?
sound quality of the result
[ "MP3\n\nWhen performing lossy audio encoding, such as creating an MP3 file, there is a trade-off between the amount of space used and the sound quality of the result. Typically, the creator is allowed to set a bit rate, which specifies how many kilobits the file may use per second of audio. The higher the bit rate,...
5706371452bb89140068996f
What would an example of lossy audio encoding be?
creating an MP3 file
[ "MP3\n\nWhen performing lossy audio encoding, such as creating an MP3 file, there is a trade-off between the amount of space used and the sound quality of the result. Typically, the creator is allowed to set a bit rate, which specifies how many kilobits the file may use per second of audio. The higher the bit rate,...
5706371452bb891400689970
Who gets to set the bit rate for an MP3 file?
the creator
[ "MP3\n\nWhen performing lossy audio encoding, such as creating an MP3 file, there is a trade-off between the amount of space used and the sound quality of the result. Typically, the creator is allowed to set a bit rate, which specifies how many kilobits the file may use per second of audio. The higher the bit rate,...
5706371452bb891400689971
What does the bit rate of the file actually mean?
how many kilobits the file may use per second of audio
[ "MP3\n\nWhen performing lossy audio encoding, such as creating an MP3 file, there is a trade-off between the amount of space used and the sound quality of the result. Typically, the creator is allowed to set a bit rate, which specifies how many kilobits the file may use per second of audio. The higher the bit rate,...
5706371452bb891400689972
If the bit rate is higher, the size of the compressed file will be what?
larger
[ "MP3\n\nWhen performing lossy audio encoding, such as creating an MP3 file, there is a trade-off between the amount of space used and the sound quality of the result. Typically, the creator is allowed to set a bit rate, which specifies how many kilobits the file may use per second of audio. The higher the bit rate,...
570637be52bb891400689978
If the bit rate is too low, what might be audible in the reproduction?
compression artifacts
[ "MP3\n\nWith too low a bit rate, compression artifacts (i.e., sounds that were not present in the original recording) may be audible in the reproduction. Some audio is hard to compress because of its randomness and sharp attacks. When this type of audio is compressed, artifacts such as ringing or pre-echo are usual...
570637be52bb891400689979
Sounds that were not in the original recording are referred to as what?
compression artifacts
[ "MP3\n\nWith too low a bit rate, compression artifacts (i.e., sounds that were not present in the original recording) may be audible in the reproduction. Some audio is hard to compress because of its randomness and sharp attacks. When this type of audio is compressed, artifacts such as ringing or pre-echo are usual...
570637be52bb89140068997a
Randomness and sharp attacks are two reasons that may make it harder to to do what to an audio file?
compress
[ "MP3\n\nWith too low a bit rate, compression artifacts (i.e., sounds that were not present in the original recording) may be audible in the reproduction. Some audio is hard to compress because of its randomness and sharp attacks. When this type of audio is compressed, artifacts such as ringing or pre-echo are usual...
570637be52bb89140068997b
Other than pre - echo, what is another example of what can happen when audio is compressed?
ringing
[ "MP3\n\nWith too low a bit rate, compression artifacts (i.e., sounds that were not present in the original recording) may be audible in the reproduction. Some audio is hard to compress because of its randomness and sharp attacks. When this type of audio is compressed, artifacts such as ringing or pre-echo are usual...
570637be52bb89140068997c
What kind of sample can display a good example of compression artifacts?
A sample of applause
[ "MP3\n\nWith too low a bit rate, compression artifacts (i.e., sounds that were not present in the original recording) may be audible in the reproduction. Some audio is hard to compress because of its randomness and sharp attacks. When this type of audio is compressed, artifacts such as ringing or pre-echo are usual...
570638d652bb891400689982
Other than the bit rate and the difficulty of the signal, what can also affect the quality of an MP3 file?
quality of the encoder
[ "MP3\n\nBesides the bit rate of an encoded piece of audio, the quality of MP3 files also depends on the quality of the encoder itself, and the difficulty of the signal being encoded. As the MP3 standard allows quite a bit of freedom with encoding algorithms, different encoders may feature quite different quality, e...
570638d652bb891400689983
The MP3 standard allows encoders to have a lot of freedom with which aspect of encoding?
encoding algorithms
[ "MP3\n\nBesides the bit rate of an encoded piece of audio, the quality of MP3 files also depends on the quality of the encoder itself, and the difficulty of the signal being encoded. As the MP3 standard allows quite a bit of freedom with encoding algorithms, different encoders may feature quite different quality, e...
570638d652bb891400689984
As a result of the freedom, different encoders can result in different quality even if which aspect of the file is the same?
bit rates
[ "MP3\n\nBesides the bit rate of an encoded piece of audio, the quality of MP3 files also depends on the quality of the encoder itself, and the difficulty of the signal being encoded. As the MP3 standard allows quite a bit of freedom with encoding algorithms, different encoders may feature quite different quality, e...
570638d652bb891400689985
An example shown has a low range quality score of what value?
2.22
[ "MP3\n\nBesides the bit rate of an encoded piece of audio, the quality of MP3 files also depends on the quality of the encoder itself, and the difficulty of the signal being encoded. As the MP3 standard allows quite a bit of freedom with encoding algorithms, different encoders may feature quite different quality, e...
570638d652bb891400689986
To compare qualities, sound files are evaluated on a scale that ranges from 1 to what?
5
[ "MP3\n\nBesides the bit rate of an encoded piece of audio, the quality of MP3 files also depends on the quality of the encoder itself, and the difficulty of the signal being encoded. As the MP3 standard allows quite a bit of freedom with encoding algorithms, different encoders may feature quite different quality, e...
57063bc552bb891400689996
How many bit rates does the simplest type of MP3 file use?
one
[ "MP3\n\nThe simplest type of MP3 file uses one bit rate for the entire file: this is known as Constant Bit Rate (CBR) encoding. Using a constant bit rate makes encoding simpler and faster. However, it is also possible to create files where the bit rate changes throughout the file. These are known as Variable Bit Ra...
57063bc552bb891400689997
What does CBR stand for?
Constant Bit Rate
[ "MP3\n\nThe simplest type of MP3 file uses one bit rate for the entire file: this is known as Constant Bit Rate (CBR) encoding. Using a constant bit rate makes encoding simpler and faster. However, it is also possible to create files where the bit rate changes throughout the file. These are known as Variable Bit Ra...
57063bc552bb891400689998
What does VBR stand for?
Variable Bit Rate
[ "MP3\n\nThe simplest type of MP3 file uses one bit rate for the entire file: this is known as Constant Bit Rate (CBR) encoding. Using a constant bit rate makes encoding simpler and faster. However, it is also possible to create files where the bit rate changes throughout the file. These are known as Variable Bit Ra...
57063bc552bb891400689999
Aside from silence, which sections of music highlight parts that are easier to compress?
music containing only a few instruments
[ "MP3\n\nThe simplest type of MP3 file uses one bit rate for the entire file: this is known as Constant Bit Rate (CBR) encoding. Using a constant bit rate makes encoding simpler and faster. However, it is also possible to create files where the bit rate changes throughout the file. These are known as Variable Bit Ra...
57063bc552bb89140068999a
What value do users need to know when encoding their music to help avoid them having to do tests on each piece of music?
quality setting
[ "MP3\n\nThe simplest type of MP3 file uses one bit rate for the entire file: this is known as Constant Bit Rate (CBR) encoding. Using a constant bit rate makes encoding simpler and faster. However, it is also possible to create files where the bit rate changes throughout the file. These are known as Variable Bit Ra...
57063c3e75f01819005e7aac
A listening environment is also know by which term?
ambient noise
[ "MP3\n\nPerceived quality can be influenced by listening environment (ambient noise), listener attention, and listener training and in most cases by listener audio equipment (such as sound cards, speakers and headphones)." ]
57063c3e75f01819005e7aad
Other than speakers and headphones, what other piece of equipment affects the listener's perceived quality?
sound cards
[ "MP3\n\nPerceived quality can be influenced by listening environment (ambient noise), listener attention, and listener training and in most cases by listener audio equipment (such as sound cards, speakers and headphones)." ]
57063c3e75f01819005e7aae
Listening environment, listener attention, listener training and listener audio equipment can all affect what kind of quality?
Perceived quality
[ "MP3\n\nPerceived quality can be influenced by listening environment (ambient noise), listener attention, and listener training and in most cases by listener audio equipment (such as sound cards, speakers and headphones)." ]
57063cb452bb8914006899a0
Who gave students a test to determine their preferences?
Music Professor Jonathan Berger
[ "MP3\n\nA test given to new students by Stanford University Music Professor Jonathan Berger showed that student preference for MP3-quality music has risen each year. Berger said the students seem to prefer the 'sizzle' sounds that MP3s bring to music." ]
57063cb452bb8914006899a1
Where was a test performed to collect data on student preference for MP3 quality?
Stanford University
[ "MP3\n\nA test given to new students by Stanford University Music Professor Jonathan Berger showed that student preference for MP3-quality music has risen each year. Berger said the students seem to prefer the 'sizzle' sounds that MP3s bring to music." ]
57063cb452bb8914006899a2
Data showed that students' preference for MP3 quality music followed which trend?
risen each year
[ "MP3\n\nA test given to new students by Stanford University Music Professor Jonathan Berger showed that student preference for MP3-quality music has risen each year. Berger said the students seem to prefer the 'sizzle' sounds that MP3s bring to music." ]
57063cb452bb8914006899a3
What kind of sound did students seem to prefer?
sizzle
[ "MP3\n\nA test given to new students by Stanford University Music Professor Jonathan Berger showed that student preference for MP3-quality music has risen each year. Berger said the students seem to prefer the 'sizzle' sounds that MP3s bring to music." ]
57063d8652bb8914006899a8
What is the name of the study done by composer Ryan Maguire?
The Ghost in the MP3
[ "MP3\n\nAn in-depth study of MP3 audio quality, sound artist and composer Ryan Maguire's project \"The Ghost in the MP3\" isolates the sounds lost during MP3 compression. In 2015, he released the track \"moDernisT\" (an anagram of \"Tom's Diner\"), composed exclusively from the sounds deleted during MP3 compression...
57063d8652bb8914006899a9
What did the study aim to isolate?
sounds lost during MP3 compression
[ "MP3\n\nAn in-depth study of MP3 audio quality, sound artist and composer Ryan Maguire's project \"The Ghost in the MP3\" isolates the sounds lost during MP3 compression. In 2015, he released the track \"moDernisT\" (an anagram of \"Tom's Diner\"), composed exclusively from the sounds deleted during MP3 compression...
57063d8652bb8914006899aa
What is the track "moDernisT" an anagram of?
Tom's Diner
[ "MP3\n\nAn in-depth study of MP3 audio quality, sound artist and composer Ryan Maguire's project \"The Ghost in the MP3\" isolates the sounds lost during MP3 compression. In 2015, he released the track \"moDernisT\" (an anagram of \"Tom's Diner\"), composed exclusively from the sounds deleted during MP3 compression...
57063d8652bb8914006899ab
Where was an account of the study published?
International Computer Music Conference
[ "MP3\n\nAn in-depth study of MP3 audio quality, sound artist and composer Ryan Maguire's project \"The Ghost in the MP3\" isolates the sounds lost during MP3 compression. In 2015, he released the track \"moDernisT\" (an anagram of \"Tom's Diner\"), composed exclusively from the sounds deleted during MP3 compression...
57063d8652bb8914006899ac
Which year was the study published?
2014
[ "MP3\n\nAn in-depth study of MP3 audio quality, sound artist and composer Ryan Maguire's project \"The Ghost in the MP3\" isolates the sounds lost during MP3 compression. In 2015, he released the track \"moDernisT\" (an anagram of \"Tom's Diner\"), composed exclusively from the sounds deleted during MP3 compression...
57063fcb52bb8914006899b2
What is the name of the sampling theorem?
Nyquist–Shannon
[ "MP3\n\nSeveral bit rates are specified in the MPEG-1 Audio Layer III standard: 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256 and 320 kbit/s, with available sampling frequencies of 32, 44.1 and 48 kHz. MPEG-2 Audio Layer III allows bit rates of 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160 kb...
57063fcb52bb8914006899b3
In relation to the sampling frequency, the frequency reproduction is strictly how much less?
less than half
[ "MP3\n\nSeveral bit rates are specified in the MPEG-1 Audio Layer III standard: 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256 and 320 kbit/s, with available sampling frequencies of 32, 44.1 and 48 kHz. MPEG-2 Audio Layer III allows bit rates of 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160 kb...
57063fcb52bb8914006899b4
What kind of filter requires a larger margin for error?
imperfect filters
[ "MP3\n\nSeveral bit rates are specified in the MPEG-1 Audio Layer III standard: 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256 and 320 kbit/s, with available sampling frequencies of 32, 44.1 and 48 kHz. MPEG-2 Audio Layer III allows bit rates of 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160 kb...
57063fcb52bb8914006899b5
Having an 8 kHz sampling rate would limit the maximum frequency to how much?
4 kHz
[ "MP3\n\nSeveral bit rates are specified in the MPEG-1 Audio Layer III standard: 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256 and 320 kbit/s, with available sampling frequencies of 32, 44.1 and 48 kHz. MPEG-2 Audio Layer III allows bit rates of 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160 kb...
57063fcb52bb8914006899b6
A sound reproduction of 24 kHz would represent which value of a maximum sampling rate?
48
[ "MP3\n\nSeveral bit rates are specified in the MPEG-1 Audio Layer III standard: 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256 and 320 kbit/s, with available sampling frequencies of 32, 44.1 and 48 kHz. MPEG-2 Audio Layer III allows bit rates of 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160 kb...
570640a275f01819005e7ac6
What sampling rate is used for CD audio?
44.1 kHz
[ "MP3\n\nA sample rate of 44.1 kHz is almost always used, because this is also used for CD audio, the main source used for creating MP3 files. A greater variety of bit rates are used on the Internet. The rate of 128 kbit/s is commonly used, at a compression ratio of 11:1, offering adequate audio quality in a relativ...
570640a275f01819005e7ac7
What is the main source used for creating MP3 files?
CD audio
[ "MP3\n\nA sample rate of 44.1 kHz is almost always used, because this is also used for CD audio, the main source used for creating MP3 files. A greater variety of bit rates are used on the Internet. The rate of 128 kbit/s is commonly used, at a compression ratio of 11:1, offering adequate audio quality in a relativ...
570640a275f01819005e7ac8
Where can one find a greater variety of bit rates?
the Internet
[ "MP3\n\nA sample rate of 44.1 kHz is almost always used, because this is also used for CD audio, the main source used for creating MP3 files. A greater variety of bit rates are used on the Internet. The rate of 128 kbit/s is commonly used, at a compression ratio of 11:1, offering adequate audio quality in a relativ...
570640a275f01819005e7ac9
The common bit rate on the internet is 128 kbit/s using which compression ratio?
11:1
[ "MP3\n\nA sample rate of 44.1 kHz is almost always used, because this is also used for CD audio, the main source used for creating MP3 files. A greater variety of bit rates are used on the Internet. The rate of 128 kbit/s is commonly used, at a compression ratio of 11:1, offering adequate audio quality in a relativ...
570640a275f01819005e7aca
As technology advances, what is another higher bit rate that is beginning to spread?
320 kbit/s
[ "MP3\n\nA sample rate of 44.1 kHz is almost always used, because this is also used for CD audio, the main source used for creating MP3 files. A greater variety of bit rates are used on the Internet. The rate of 128 kbit/s is commonly used, at a compression ratio of 11:1, offering adequate audio quality in a relativ...
5706414c75f01819005e7ad0
What is stored on an audio-CD that has a bit rate of 1,411.2 kbit/s?
Uncompressed audio
[ "MP3\n\nUncompressed audio as stored on an audio-CD has a bit rate of 1,411.2 kbit/s, (16 bit/sample × 44100 samples/second × 2 channels / 1000 bits/kilobit), so the bitrates 128, 160 and 192 kbit/s represent compression ratios of approximately 11:1, 9:1 and 7:1 respectively." ]
5706414c75f01819005e7ad1
What does a bit rate of 128 represent in terms of compression ratio?
11:1
[ "MP3\n\nUncompressed audio as stored on an audio-CD has a bit rate of 1,411.2 kbit/s, (16 bit/sample × 44100 samples/second × 2 channels / 1000 bits/kilobit), so the bitrates 128, 160 and 192 kbit/s represent compression ratios of approximately 11:1, 9:1 and 7:1 respectively." ]
5706414c75f01819005e7ad2
What would a bit rate of 160 correspond to in terms of compression ratio?
9:1
[ "MP3\n\nUncompressed audio as stored on an audio-CD has a bit rate of 1,411.2 kbit/s, (16 bit/sample × 44100 samples/second × 2 channels / 1000 bits/kilobit), so the bitrates 128, 160 and 192 kbit/s represent compression ratios of approximately 11:1, 9:1 and 7:1 respectively." ]
5706414c75f01819005e7ad3
What would a bit rate of 192 kbit/s have for a compression ratio?
7:1
[ "MP3\n\nUncompressed audio as stored on an audio-CD has a bit rate of 1,411.2 kbit/s, (16 bit/sample × 44100 samples/second × 2 channels / 1000 bits/kilobit), so the bitrates 128, 160 and 192 kbit/s represent compression ratios of approximately 11:1, 9:1 and 7:1 respectively." ]
570641f775f01819005e7ad8
What is the highest bit rate the LAME encoder allows?
640 kbit/s
[ "MP3\n\nNon-standard bit rates up to 640 kbit/s can be achieved with the LAME encoder and the freeformat option, although few MP3 players can play those files. According to the ISO standard, decoders are only required to be able to decode streams up to 320 kbit/s." ]
570641f775f01819005e7ad9
The LAME encoder allows bit rates that are what?
Non-standard
[ "MP3\n\nNon-standard bit rates up to 640 kbit/s can be achieved with the LAME encoder and the freeformat option, although few MP3 players can play those files. According to the ISO standard, decoders are only required to be able to decode streams up to 320 kbit/s." ]
570641f775f01819005e7ada
Even though few MP3 players can play it, LAME also offers which option?
freeformat
[ "MP3\n\nNon-standard bit rates up to 640 kbit/s can be achieved with the LAME encoder and the freeformat option, although few MP3 players can play those files. According to the ISO standard, decoders are only required to be able to decode streams up to 320 kbit/s." ]
570641f775f01819005e7adb
The ISO standard dictates that decoders only need to be able to decode streams that have how high of a bit rate?
320
[ "MP3\n\nNon-standard bit rates up to 640 kbit/s can be achieved with the LAME encoder and the freeformat option, although few MP3 players can play those files. According to the ISO standard, decoders are only required to be able to decode streams up to 320 kbit/s." ]
5706443e75f01819005e7ae0
What does the term CBR mean?
Constant Bit Rate
[ "MP3\n\nEarly MPEG Layer III encoders used what is now called Constant Bit Rate (CBR). The software was only able to use a uniform bitrate on all frames in an MP3 file. Later more sophisticated MP3 encoders were able to use the bit reservoir to target an average bit rate selecting the encoding rate for each frame b...
5706443e75f01819005e7ae1
Which early MPEG layer used CBR?
Layer III
[ "MP3\n\nEarly MPEG Layer III encoders used what is now called Constant Bit Rate (CBR). The software was only able to use a uniform bitrate on all frames in an MP3 file. Later more sophisticated MP3 encoders were able to use the bit reservoir to target an average bit rate selecting the encoding rate for each frame b...
5706443e75f01819005e7ae2
The early software was restricted to which kind of bitrate?
uniform
[ "MP3\n\nEarly MPEG Layer III encoders used what is now called Constant Bit Rate (CBR). The software was only able to use a uniform bitrate on all frames in an MP3 file. Later more sophisticated MP3 encoders were able to use the bit reservoir to target an average bit rate selecting the encoding rate for each frame b...
5706443e75f01819005e7ae3
What did more sophisticated MP3 encoders use to target an average bit rate?
bit reservoir
[ "MP3\n\nEarly MPEG Layer III encoders used what is now called Constant Bit Rate (CBR). The software was only able to use a uniform bitrate on all frames in an MP3 file. Later more sophisticated MP3 encoders were able to use the bit reservoir to target an average bit rate selecting the encoding rate for each frame b...
5706443e75f01819005e7ae4
What did encoders base the encoding rate for each frame on?
the complexity of the sound
[ "MP3\n\nEarly MPEG Layer III encoders used what is now called Constant Bit Rate (CBR). The software was only able to use a uniform bitrate on all frames in an MP3 file. Later more sophisticated MP3 encoders were able to use the bit reservoir to target an average bit rate selecting the encoding rate for each frame b...
5706457d75f01819005e7aea
What kind of audio can a sophisticated MP3 encoder produce?
variable bitrate audio
[ "MP3\n\nA more sophisticated MP3 encoder can produce variable bitrate audio. MPEG audio may use bitrate switching on a per-frame basis, but only layer III decoders must support it. VBR is used when the goal is to achieve a fixed level of quality. The final file size of a VBR encoding is less predictable than with c...
5706457d75f01819005e7aeb
Which type of decoder must support bitrate switching on a per-frame basis?
layer III
[ "MP3\n\nA more sophisticated MP3 encoder can produce variable bitrate audio. MPEG audio may use bitrate switching on a per-frame basis, but only layer III decoders must support it. VBR is used when the goal is to achieve a fixed level of quality. The final file size of a VBR encoding is less predictable than with c...
5706457d75f01819005e7aec
What do encoders use when the goal is to achieve a fixed level of quality?
VBR
[ "MP3\n\nA more sophisticated MP3 encoder can produce variable bitrate audio. MPEG audio may use bitrate switching on a per-frame basis, but only layer III decoders must support it. VBR is used when the goal is to achieve a fixed level of quality. The final file size of a VBR encoding is less predictable than with c...
5706457d75f01819005e7aed
Using VBR instead of a constant bit rate encoding makes which part of encoding less predictable?
final file size
[ "MP3\n\nA more sophisticated MP3 encoder can produce variable bitrate audio. MPEG audio may use bitrate switching on a per-frame basis, but only layer III decoders must support it. VBR is used when the goal is to achieve a fixed level of quality. The final file size of a VBR encoding is less predictable than with c...
5706457d75f01819005e7aee
An average bit rate is used when who choses an average value for the encoder to use?
the user
[ "MP3\n\nA more sophisticated MP3 encoder can produce variable bitrate audio. MPEG audio may use bitrate switching on a per-frame basis, but only layer III decoders must support it. VBR is used when the goal is to achieve a fixed level of quality. The final file size of a VBR encoding is less predictable than with c...
570646b852bb8914006899bc
A partially full frame's ability to have part of the next frame's audio data is referred to as what?
bit reservoir
[ "MP3\n\nLayer III audio can also use a \"bit reservoir\", a partially full frame's ability to hold part of the next frame's audio data, allowing temporary changes in effective bitrate, even in a constant bitrate stream. Internal handling of the bit reservoir increases encoding delay.[citation needed]" ]
570646b852bb8914006899bd
What kind of audio is required to use a bit reservoir?
Layer III
[ "MP3\n\nLayer III audio can also use a \"bit reservoir\", a partially full frame's ability to hold part of the next frame's audio data, allowing temporary changes in effective bitrate, even in a constant bitrate stream. Internal handling of the bit reservoir increases encoding delay.[citation needed]" ]
570646b852bb8914006899be
A bit reservoir allows for what kind of changes in effective bit rate?
temporary
[ "MP3\n\nLayer III audio can also use a \"bit reservoir\", a partially full frame's ability to hold part of the next frame's audio data, allowing temporary changes in effective bitrate, even in a constant bitrate stream. Internal handling of the bit reservoir increases encoding delay.[citation needed]" ]
570646b852bb8914006899bf
What is a possible result of handling the bit reservoir?
encoding delay
[ "MP3\n\nLayer III audio can also use a \"bit reservoir\", a partially full frame's ability to hold part of the next frame's audio data, allowing temporary changes in effective bitrate, even in a constant bitrate stream. Internal handling of the bit reservoir increases encoding delay.[citation needed]" ]
570646b852bb8914006899c0
A large benefit of a bit reservoir is that you can use it even while encoding what kind of stream?
constant bitrate
[ "MP3\n\nLayer III audio can also use a \"bit reservoir\", a partially full frame's ability to hold part of the next frame's audio data, allowing temporary changes in effective bitrate, even in a constant bitrate stream. Internal handling of the bit reservoir increases encoding delay.[citation needed]" ]
5706493c52bb8914006899c6
What can scale factor band 21 be shortened to?
sfb21
[ "MP3\n\nThere is no scale factor band 21 (sfb21) for frequencies above approx 16 kHz, forcing the encoder to choose between less accurate representation in band 21 or less efficient storage in all bands below band 21, the latter resulting in wasted bitrate in VBR encoding." ]
5706493c52bb8914006899c7
What is the maximum frequency that scale factor band 21 can go up to?
16 kHz
[ "MP3\n\nThere is no scale factor band 21 (sfb21) for frequencies above approx 16 kHz, forcing the encoder to choose between less accurate representation in band 21 or less efficient storage in all bands below band 21, the latter resulting in wasted bitrate in VBR encoding." ]
5706493c52bb8914006899c8
The encoder has to choose between less acurate representation in band 21 or which factor in all bands below band 21?
less efficient storage
[ "MP3\n\nThere is no scale factor band 21 (sfb21) for frequencies above approx 16 kHz, forcing the encoder to choose between less accurate representation in band 21 or less efficient storage in all bands below band 21, the latter resulting in wasted bitrate in VBR encoding." ]
5706493c52bb8914006899c9
What does less efficient storage result in for VBR encoding?
wasted bitrate
[ "MP3\n\nThere is no scale factor band 21 (sfb21) for frequencies above approx 16 kHz, forcing the encoder to choose between less accurate representation in band 21 or less efficient storage in all bands below band 21, the latter resulting in wasted bitrate in VBR encoding." ]
57064bd375f01819005e7b12
What is a section of a file that contains metadeta referred to as?
tag
[ "MP3\n\nA \"tag\" in an audio file is a section of the file that contains metadata such as the title, artist, album, track number or other information about the file's contents. The MP3 standards do not define tag formats for MP3 files, nor is there a standard container format that would support metadata and obviat...
57064bd375f01819005e7b13
What else can metadeta contain other than the title, artist or track number?
album
[ "MP3\n\nA \"tag\" in an audio file is a section of the file that contains metadata such as the title, artist, album, track number or other information about the file's contents. The MP3 standards do not define tag formats for MP3 files, nor is there a standard container format that would support metadata and obviat...
57064bd375f01819005e7b14
What do MP3 standards not define?
tag formats for MP3 files
[ "MP3\n\nA \"tag\" in an audio file is a section of the file that contains metadata such as the title, artist, album, track number or other information about the file's contents. The MP3 standards do not define tag formats for MP3 files, nor is there a standard container format that would support metadata and obviat...
57064bd375f01819005e7b15
What would be needed to support metadata and obviate the need for tags?
a standard container format
[ "MP3\n\nA \"tag\" in an audio file is a section of the file that contains metadata such as the title, artist, album, track number or other information about the file's contents. The MP3 standards do not define tag formats for MP3 files, nor is there a standard container format that would support metadata and obviat...
57064d5075f01819005e7b2a
Other than the ID3v1, which similar standard format for tag exists?
ID3v2
[ "MP3\n\nHowever, several de facto standards for tag formats exist. As of 2010, the most widespread are ID3v1 and ID3v2, and the more recently introduced APEv2. These tags are normally embedded at the beginning or end of MP3 files, separate from the actual MP3 frame data. MP3 decoders either extract information from...
57064d5075f01819005e7b2b
What is the most recently introduced standard for tag formatting?
APEv2
[ "MP3\n\nHowever, several de facto standards for tag formats exist. As of 2010, the most widespread are ID3v1 and ID3v2, and the more recently introduced APEv2. These tags are normally embedded at the beginning or end of MP3 files, separate from the actual MP3 frame data. MP3 decoders either extract information from...
57064d5075f01819005e7b2c
What is the second place in a file that tags are normally stored, with the first being at the beginning?
end
[ "MP3\n\nHowever, several de facto standards for tag formats exist. As of 2010, the most widespread are ID3v1 and ID3v2, and the more recently introduced APEv2. These tags are normally embedded at the beginning or end of MP3 files, separate from the actual MP3 frame data. MP3 decoders either extract information from...