Decode (<B><TT>flac</TT></B> encodes by default). <B><TT>flac</TT></B> will exit with an exit code of <TT>1</TT> (and print a message, even in silent mode) if there were any errors during decoding, including when the MD5 checksum does not match the decoded output. Otherwise the exit code will be <TT>0</TT>.
Analyze (same as <B><TT>-d</TT></B> except an analysis file is written). The exit codes are the same as in decode mode. This option is mainly for developers; the output will be a text file that has data about each frame and subframe.
Force the output file name (usually <TT><B>flac</B></TT> just changes the extension). May only be used when encoding a single file. May not be used in conjunction with <TT>--output-prefix</T>.
Prefix each output file name with the given string. This can be useful for encoding/decoding files to a different directory. Make sure if your string is a path name that it ends with a trailing '<TT>/</TT>' slash.
By default <B><TT>flac</TT></B> stops decoding with an error and removes the partially decoded file if it encounters a bitstream error. With <TT>-F</TT>, errors are still printed but <B><TT>flac</TT></B> will continue decoding to completion. Note that errors may cause the decoded audio to be missing some samples or have silent sections.
Verify the encoding process. With this option, <B><TT>flac</TT></B> will create a parallel decoder that decodes the output of the encoder and compares the result against the original. It will abort immediately with an error if a mismatch occurs. <B><TT>-V</TT></B> increases the total encoding time but is guaranteed to catch any unforseen bug in the encoding process.
Tell the encoder to write a <TT>PADDING</TT> metadata block of the given length (in bytes) after the <TT>STREAMINFO</TT> block. This is useful if you plan to tag the file later with an <TT>APPLICATION</TT> block; instead of having to rewrite the entire file later just to insert your block, you can write directly over the <TT>PADDING</TT> block. Note that the total length of the <TT>PADDING</TT> block will be 4 bytes longer than the length given because of the 4 metadata block header bytes. You can force no <TT>PADDING</TT> block at all to be written with <TT>-P-</TT>, which is the default.
Specify the block size in samples. The default is 1152 for -l 0, otherwise 4608. Subset streams must use one of 192/576/1152/2304/4608/256/512/1024/2048/4096/8192/16384/32768. The reference encoder uses the same block size for the entire stream.
Enable mid-side coding (only for stereo streams). Tends to increase compression by a few percent on average. For each block both the stereo pair and mid-side versions of the block will be encoded, and smallest resulting frame will be stored. Currently mid-side encoding is only available when bits-per-sample <=16.
Enable loose mid-side coding (only for stereo streams). Like <TT>-m</TT> but the encoder adaptively switches between independent and mid-side coding, which is faster but yields less compression than <TT>-m</TT> (which does an exhaustive search).
Enable adaptive mid-side coding (only for stereo streams). Like <TT>-m</TT> but the encoder adaptively switches between independent and mid-side coding, which is faster but yields less compression than <TT>-m</TT> (which does an exhaustive search).
Exhaustive model search (expensive!). Normally the encoder estimates the best model to use and encodes once based on the estimate. With an exhaustive model search, the encoder will generate subframes for every order and use the smallest. If the max LPC order is high this can significantly increase the encode time but can shave off another 0.5%.
Do escape coding in the entropy coder. This causes the encoder to use an unencoded representation of the residual in a partition if it is smaller. It increases the runtime and usually results in an improvement of less than 1%.
Specifies the maximum LPC order. This number must be <=32.If0,theencoderwillnotattemptgenericlinearprediction,anduseonlyfixedpredictors.Usingfixedpredictorsisfasterbutusuallyresultsinfilesbeing5-10%larger.
Specifies the precision of the quantized LP coefficients, in bits. The default is <B><TT>-q 0</TT></B>, which means let the encoder decide based on the signal. Unless you really know your input file it's best to leave this up to the encoder.
Do exhaustive LP coefficient quantization optimization. This option overrides any <B><TT>-q</TT></B> option. It is expensive and typically will only improve the compression a tiny fraction of a percent. <B><TT>-q</TT></B> has no effect when <B><TT>-l 0</TT></B> is used.
Verify the encoding process. With this option, <B><TT>flac</TT></B> will create a parallel decoder that decodes the output of the encoder and compares the result against the original. It will abort immediately with an error if a mismatch occurs. <B><TT>-V</TT></B> increases the total encoding time but is guaranteed to catch any unforseen bug in the encoding process.
<TT>-F-</TT>, <TT>-S-</TT>, <TT>-P-</TT>, <TT>-m-</TT>, <TT>-e-</TT>, <TT>-E-</TT>, <TT>-p-</TT>, <TT>-V-</TT>, <TT>--delete-input-file-</TT>, <TT>--lax-</TT>, <TT>--sector-align-</TT>can all be used to turn off a particular option.
