| 目前市面上有两种内存条，registered 和 unbuffered。它们是不能混插在同一服务器中的。所有的低端X系列服务器现在都使用registered SDRAM 内存。 安装unbuffered同存条，内存控制器直接与DRAMs（动态随机存储控制器）通讯，比registered内存具有轻微的性能优势。Unbuffered内存的劣势是它们具有有限的驱动容量，这意味着大量的内存条连接在同一总线上仍具有较小的容量，因为电子负荷。 Registered内存的不同点是，使用registers（寄存器）将内存控制器与DRAMs（动态随机存储控制器）隔离开。这带来了更轻的电子负荷，因此这使得更多的内存条可以相连接，实现了更大的内存容量。register（寄存器）一般会增加时钟或延迟，意味着registered内存相比于unbuffered内存条需要更长的访问时间。 这些不同意味着通常在设计时，系统所支持的unbuffered内存条比registered要少，这对于台式机来讲不是问题，服务器经常需要大容量的同存所以一般选用registered内存条。 |
| SPHERE Header Example: NIST_1A 1024 database_id -s3 RM1 database_version -s3 1.0 utterance_id -s11 aks0_st0783 channel_count -i 1 sample_count -i 50074 sample_rate -i 16000 sample_min -i -2032 sample_max -i 2708 sample_n_bytes -i 2 sample_byte_format -s2 01 sample_sig_bits -i 16 end_head (binary audio data follows) | Explanation: (type of header) (size of header) (databse type) (database version) (utterance identifier) (number of channels) (number of samples) (sample rate) (minimum amplitude) (maximum amplitude) (number of bytes per sample) (byte format:01: little endian; 10: big endian) (number of bits per sample) (ends the header) (signed short integer-valued data) |
NIST_1A<new-line> 1024<new-line>The first line specifies the header type and the second line specifies the header length. Each of these lines are 8 bytes long (including new-line) and are structured to identify the header as well as allow those who do not wish to read the subsequent header information to programmatically skip over it.The remaining object-oriented variable portion is composed of object-type-value "triple" lines which have the following format:
<LINE> ::= <TRIPLE><new-line> |
<COMMENT><new-line> |
<TRIPLE><COMMENT><new-line> |
<TRIPLE> ::= <OBJECT><space><TYPE><space><VALUE><OPT-SPACES>
<OBJECT> ::= <PRIMARY-SUBOBJECT> |
<PRIMARY-SUBOBJECT><SECONDARY-SUBOBJECT>
<PRIMARY-SUBOBJECT> ::= <ALPHA> | <ALPHA><ALPHA-NUM-STRING>
<SECONDARY-SUBOBJECT> ::= _<ALPHA-NUM-STRING> |
_<ALPHA-NUM-STRING><SECONDARY-SUBOBJECT>
<TYPE> ::= -<INTEGER-FLAG> | -<REAL-FLAG> | -<STRING-FLAG>
<INTEGER-FLAG> ::= i
<REAL-FLAG> ::= r
<STRING-FLAG> ::= s<DIGIT-STRING>
<VALUE> ::= <INTEGER> | <REAL> | <STRING> (depending on object type)
<INTEGER> ::= <SIGN><DIGIT-STRING>
<REAL> ::= <SIGN><DIGIT-STRING>.<DIGIT-STRING>
<OPT-SPACES> ::= <SPACES> | NULL
<COMMENT> ::= ;<STRING> (excluding embedded new-lines)
<ALPHA-NUM-STRING> ::= <ALPHA-NUM> | <ALPHA-NUM><ALPHA-NUM-STRING>
<ALPHA-NUM> ::= <DIGIT> | <ALPHA>
<ALPHA> ::= a | ... | z | A | ... | Z
<DIGIT-STRING> ::= <DIGIT> | <DIGIT><DIGIT-STRING>
<DIGIT> ::= 0 | ... | 9
<SIGN> ::= + | - | NULL
<SPACES> ::= <space> | <SPACES><space>
<STRING> ::= <CHARACTER> | <CHARACTER><STRING>
<CHARACTER> ::= char(0) | char(1) | ... | char(255)
Note: The grammar does not impose any limit on the number or order of objects.The single object "end_head" marks the end of the active header and the remaining unused header space is undefined.Field Type Description - Probable defaults marked in ()
----------------------- ------- ---------------------------------------------
speaker_id string 3-char. speaker ID from filename
speaking_mode string speaking mode ("spontaneous" or "read")
recording_date string beginning of recording date stamp of the
form DD-MMM-YYYY. Should contain the string
"unknown" if this info is not available.
recording_time -s11 string beginning of recording time stamp of the
form HH:MM:SS.HH. Should contain the string
"unknown" if this info is not available.
microphone string microphone description ("Sennheiser HMD-410"
or "Crown PCC-160")
utterance_id string utterance ID from filename of the form
XXXUUSMP as described in the filenames
specification document.
database_id string database (corpus) identifier ("atis3")
database_version string database (corpus) revision ("1.0")
channel_count integer number of channels in waveform ("1")
speaker_session_number string 1-char. scenario-session ID from filename
sample_count integer number of samples in waveform
sample_max integer maximum sample value in waveform
sample_min integer minimum sample value in waveform
sample_rate integer waveform sampling rate ("16000")
sample_n_bytes integer number of bytes per sample ("2")
sample_byte_format string byte order (MSB/LSB -> "10" or
LSB/MSB -> "01")
sample_sig_bits integer number of significant bits in each sample
("16")
session_utterance_number integer base-10 version of "speaker_sentence_number"
speaker_sentence_number string 2-character query within scenario-session
(base 36) from filename
end_head none end of header identifier
Note: Although these fields are mandatory, you may include additional local fields if you wish. If you do add fields, please email us the field names and types so that we can add them to our library.Hypothetical ATIS3 header:NIST_1A 1024 speaker_id -s3 z01 (speaker ID "z01") speaking_mode -s11 spontaneous (spontaneous speaking mode) recording_date -s11 17-APR-1993 (date of beginning of recording) recording_time -s11 10:23:39.79 (time of beginning of recording) microphone -s18 Sennheiser HMD-410 (microphone description) utterance_id -s8 z010b1ss (utterance ID from filename) database_id -s5 atis3 (corpus ID "atis3") database_version -s3 1.0 (utterance release "1.0") channel_count -i 1 (single-channel waveform) speaker_session_number -s1 1 (scenario-session 1 for speaker) sample_count -i 215040 (number of samples in waveform) sample_max -i 1115 (maximum sample value) sample_min -i -1479 (minimum sample value) sample_rate -i 16000 (16 kHz. sampling rate) sample_n_bytes -i 2 (2-bytes per sample) sample_byte_format -s2 10 (MSB/LSB byte order) sample_sig_bits -i 16 (16 significant bits per sample) session_utterance_number -i 11 (scenario-session query 11, base 10) speaker_sentence_number -s3 0b (scenario-session query 0b, base 36) end_headThe speech waveform data follows the header and should contain single-channel 16-bit linear quantized samples at 16kHz. sample rate. There should be no "gain normalization" or post-processing of the the waveform data.