| 1 | The 0.5 TMuC release introduces new unified config file and command line |
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| 2 | parsing code. This allows all configuration file options to be specified |
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| 3 | on the command line and permits the use of multiple config files. |
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| 4 | |
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| 5 | Compatability with command line options in previous TMuC releases is |
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| 6 | maintained with the following exceptions: |
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| 7 | - Commandline -1/-0 FEN does not implicitly set ASR, |
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| 8 | this now matches the behaviour of the config file. |
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| 9 | - FramesToBeEncoded is now the preferred name for FrameToBeEncoded |
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| 10 | (the old option still exists for compatibility) |
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| 11 | - Commandline & Config, setting of GOPSize nolonger unconditionally |
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| 12 | sets RateGOPSize. If RateGOPSize is never set, it assumes as its |
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| 13 | default value, the value of GOPSize. |
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| 14 | |
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| 15 | Unless it is specifically required, do not set the RateGOPSize to a |
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| 16 | value other than -1. This value (the default) causes RateGOPSize |
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| 17 | to inherit the final value of GOPSize. While setting config files |
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| 18 | to have RateGOPSize = GOPSize does no immediate harm, it causes |
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| 19 | confusion when GOPSize is altered (without altering RateGOPSize) and |
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| 20 | behaviour changes relating to GPB. |
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| 21 | |
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| 22 | All configuration options may be specified on the command line using the |
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| 23 | following syntax: |
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| 24 | --CfgOptionName=value |
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| 25 | For example, |
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| 26 | --InputFile=Kimono1_1920x1080_24.yuv |
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| 27 | |
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| 28 | A list of all options avaliable is provided by running the encoder with |
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| 29 | either no options, or the option "--help". |
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| 30 | |
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| 31 | The command line is evaluated in the order of options given, for example: |
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| 32 | ./encoder -c file1.cfg --UseFoo=7 -c file2.cfg |
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| 33 | |
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| 34 | The following may be observed: |
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| 35 | - file2.cfg overrides any arguments set in file1. |
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| 36 | - file1.cfg overrides any default arguments |
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| 37 | - if file2.cfg specifies "UseFoo", this value will be used |
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| 38 | otherwise, "UseFoo" will have the value 7. |
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| 39 | |
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| 40 | ==================== |
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| 41 | Notes for developers |
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| 42 | ==================== |
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| 43 | The new unified config file and command line parsing code allows all |
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| 44 | configuration options, storage location, defaults, help text to be specified |
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| 45 | in a single place. No custom value parsing code is required. |
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| 46 | |
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| 47 | Options are specified in TAppEncCfg::parseCfg() using the following syntax: |
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| 48 | {{{ |
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| 49 | /* storage for options */ |
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| 50 | int storage_variable_int; |
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| 51 | unsigned storage_variable_unsigned; |
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| 52 | float storage_variable_float; |
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| 53 | bool storage_variable_bool; |
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| 54 | string storage_variable_string; |
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| 55 | |
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| 56 | /* set up configuration */ |
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| 57 | namespace po = df::program_options_lite; |
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| 58 | po::Options opts; |
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| 59 | opts.addOptions() |
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| 60 | /*( option spec , reference to storage, default, help text)*/ |
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| 61 | ("option_spec0", storage_variable_int, -42, "help text") |
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| 62 | ("option_spec1", storage_variable_unsigned, 17u, "help text") |
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| 63 | ("option_spec2", storage_variable_bool, true, "help text") |
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| 64 | ("option_spec3", storage_variable_float, 4.0f, "help text") |
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| 65 | ("option_spec4", storage_variable_string, string("foo"), "help text") |
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| 66 | ; |
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| 67 | }}} |
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| 68 | |
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| 69 | NB, the help text is optional. |
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| 70 | |
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| 71 | Where, the option_spec is a string containing comma separated names in |
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| 72 | the following forms: |
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| 73 | - multi-charcter names are longopts that are handled in gnu style |
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| 74 | (and may be handled in a config file) |
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| 75 | - single-character names are short opts that are handled in posix style |
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| 76 | (and are not handled in a config file) |
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| 77 | prefixing a multi-character name stops it being handled in the config. |
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| 78 | |
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| 79 | For example: |
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| 80 | option spec | config file formats | command line formats |
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| 81 | "Name" | Name:value | --Name=value |
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| 82 | "n" | --none-- | -n value |
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| 83 | "-name" | --none-- | -name value |
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| 84 | "Name,n" | Name:value | "--Name=value" or "-n value" |
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| 85 | |
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| 86 | Caveats: |
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| 87 | - The default values need to be specified in the same type as the storage |
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| 88 | variable. Eg, an unsigned int, would need to be specified as "17u" not |
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| 89 | "17" |
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| 90 | |
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| 91 | Help text formatting: |
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| 92 | - Help text will be automatically wrapped and aligned if longer than the |
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| 93 | available space. |
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| 94 | - To force wrapping at a particular point, insert a newline character '\n' |
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| 95 | Eg: "Foo values:\n value1 - a\n value2 - b\n value3 - c" |
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| 96 | Gives: |
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| 97 | Foo values: |
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| 98 | value1 - a |
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| 99 | value2 - b |
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| 100 | value3 - c |
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| 101 | |
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| 102 | Please report any issues, or requests for support with the configuration to: |
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| 103 | David Flynn <davidf@rd.bbc.co.uk> |
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