manual/configure_rockbox/recording_settings.tex

   1 % $Id:$ %
   2 \screenshot{main_menu/images/ss-recording-settings}{The recording settings screen}{}
   3
   4 \note{To change the location where recordings are stored open the
   5       \setting{Context Menu} (see \reference{ref:Contextmenu}) on the directory
   6       where you want to store them in the \setting{File Browser} and select
   7       \setting{Set As Recording Directory}.}
   8
   9 \opt{MASCODEC}{
  10   \section{Quality}
  11     Choose the quality here (0 to 7). Default is 5, best quality is 7,
  12     smallest file size is 0. This setting effects how much your sound
  13     sample will be compressed. Higher quality settings result in larger
  14     MP3 files.
  15
  16     The quality setting is just a way of selecting an average bit rate,
  17     or number of  bits per second, for a recording.  When  this setting
  18     is lowered, recordings are compressed more (meaning worse sound quality),
  19     and the average bitrate changes as follows.
  20
  21   \begin{table}[h!]
  22     \begin{center}
  23       \begin{tabularx}{0.75\textwidth}{lX}\toprule
  24         \emph{Frequency} & \emph{Bitrate} (Kbit/s) -- quality 0$\rightarrow$7 \\\midrule
  25         44100Hz stereo   & 75, 80, 90, 100, 120, 140, 160, 170 \\
  26         22050Hz stereo   & 39, 41, 45, 50,  60,  80,  110, 130 \\
  27         44100Hz mono     & 65, 68, 73, 80,  90,  105, 125, 140 \\
  28         22050Hz mono     & 35, 38, 40, 45,  50,  60,  75,  90 \\\bottomrule
  29       \end{tabularx}
  30     \end{center}
  31   \end{table}
  32 }
  33
  34 \opt{swcodec}{
  35   \section{Format}
  36     Choose which format to save your recording in. The available choices are
  37     the two uncompressed formats \setting{PCM Wave} and \setting{AIFF}, the
  38     losslessly compressed \setting{WavPack} and the lossy
  39         \setting{MPEG Layer 3}.
  40
  41   \section{Encoder Settings}
  42     This sets the bitrate when using the \setting{MPEG Layer 3} format. And has
  43     no settings for the other formats.
  44 }
  45
  46   \section{Frequency}
  47    \nopt{sansa}{
  48     Choose the recording frequency (sample rate).
  49     \opt{MASCODEC}{48kHz, 44.1kHz, 32kHz, 24kHz, 22.05kHz, 16kHz}
  50     \opt{h100,h300}{44.1kHz, 22.05kHz and 11.025kHz}
  51     \opt{x5}{88.2kHz, 44.1kHz, 22.05kHz and 11.025kHz}
  52     are available. Higher sample rates use up more disk space, but give better
  53     sound quality.
  54     \opt{swcodec}{\note{The 11.025kHz setting is not available when using%
  55       \setting{MPEG Layer 3} format.}
  56     }%
  57     \opt{MASCODEC}{
  58       The frequency setting also determines which version of the MPEG standard
  59       the sound is recorded using:\\
  60       MPEG v1 for 48, 44.1 and 32\\
  61       MPEG v2 for 24, 22.05 and 16\\
  62     }
  63     \opt{recorder,recorderv2fm,h100}
  64       {\note{You cannot change the sample rate for digital recordings.}
  65     }
  66    } % nopt e200
  67    \opt{e200}{
  68        Recordings can only be made at a 22.05kHz frequency (sample rate)
  69          on this \dap.
  70     } % opt e200
  71
  72 \section{Source}
  73   Choose the source of the recording. The options are:
  74   \opt{recorder,recorderv2fm,h100}{\setting{SPDIF (digital)}, }%
  75   \nopt{ipodnano,ipodvideo}{\setting{Mic}}%
  76   \nopt{sansa}{, and {\setting{Line In}}}. %
  77   \opt{radio}{For recording from the radio see \reference{ref:FMradio}.}
  78
  79 \section{Channels}
  80   This allows you to select mono or stereo recording. Please note that
  81   for mono recording, only the left channel is recorded. Mono recordings
  82   are usually somewhat smaller than stereo.
  83
  84 \opt{swcodec}{
  85   \section{Mono Mode}
  86     When configured to record to mono and the source is a stereo signal, use this
  87     setting to configure how the mono signal is created. Options are L, R and L+R.
  88 }
  89
  90 \opt{MASCODEC}{
  91   \section{Independent Frames}
  92     The independent frames option tells the \dap{} to encode with the bit
  93     reservoir disabled, so the frames are independent of each other. This
  94     makes a file easier to edit.
  95 }
  96
  97 \section{File Split Options}
  98   This sub menu contains options for file splitting, which can be used to split
  99   up long recordings into manageable pieces. The splits are seamless (frame
 100   accurate), no audio is lost at the split point. The break between recordings
 101   is only the time required to stop and restart the recording, on the order of
 102   2 -- 4 seconds.
 103   \begin{description}
 104     \item[Split Measure:]
 105       This option controls wether to split the recording when the
 106       \setting{Split Filesize} is reached or when the
 107       \setting{Split Time} has elapsed.
 108
 109     \item[What to do when Splitting:]
 110       This controls what will happend when the splitting condition is
 111       fullfilled the two available options here are
 112       \setting{Start a new file} or \setting{Stop recording}.
 113
 114     \item[Split Time:]
 115       Set the time to record between each split, if time is used as
 116       \setting{Split Measure}.\\
 117       Options (hours:minutes between splits): Off, 00:05, 00:10, 00:15, 00:30,
 118       1:00, 1:14 (74 minute  CD), 1:20 (80 minute CD), 2:00, 4:00, 8:00, 10:00,
 119       12:00, 18:00, 24:00.
 120
 121     \item[Split Filesize:]
 122       Set the filesize to record between each split, if filesize is used as
 123       \setting{Split Measure}.
 124
 125   \end{description}
 126
 127 \section{Prerecord Time}
 128     This setting buffers a small amount of audio so that when the record button
 129     is pressed, the recording will begin from that number of seconds earlier.
 130     This is useful for ensuring that a recording begins before a cue that is
 131     being waited for.
 132
 133 \section{Clear Recording Directory}
 134     Resets the location where the recorded files are saved to the root of your
 135     \daps{} drive.
 136
 137 \nopt{ondio}{
 138   \section{Clipping Light}
 139     Causes the backlight to flash on when clipping has been detected.\\
 140     Options: \setting{Off}, \setting{Main unit only},
 141     \setting{Main and remote unit}, \setting{Remote unit only}.
 142 }
 143 \section{Trigger}
 144   When you record a source you often are only interested in the sound and not
 145   the silence in between. The recording trigger provides you with a
 146   tool to automatically distinguish between sound and silence and record the
 147   sound only.  Unfortunately it is not very easy to make this distinction between
 148   silence and sound because you hardly ever encounter real silence. There always
 149   are background noises. What is considered as background noise depends on the
 150   situation. For example during a lecture the very low noise of rustling paper
 151   might be considered as background noise. During a rock concert the murmur of
 152   the audience might be concidered background noise which is much louder compared
 153   to rustling paper. Also the duration of the signal matters. When you record
 154   speech you want to record every syllable. When you record live music you may
 155   not be interested in that chord the guitarist strokes for two minutes before
 156   the show to verify his amp is turned on. The trigger features numerous
 157   parameters to adapt its behaviour to the desired situation.
 158   \begin{description}
 159   \item[Trigger]
 160         This parameter specifies the trigger mode.  When set to \setting{Off}
 161         the recording must be started manually and apart from the Prerecord time no
 162         other parameter has any effect.  \setting{Once} will have the trigger start
 163         one recording only; after the recording has finished the input signal will
 164         not start another recording. \setting{Repeat} will have the trigger start
 165         multiple recordings.
 166
 167   \item[Trigtype]
 168     \fixme{Add description of Trigtype}
 169         Options: \setting{Stop}, \setting{Pause}, \setting{New File}.
 170
 171   \item[Prerecord Time]
 172     This specifies the time that is included into the recording before the
 173         trigger event occurs. This is very useful if you record a signal that fades
 174         in. Usually you want to set the prerecord time >= start duration. That
 175         ensures that you record the entire sound. Strictly speaking the prerecord
 176         time is not a special parameter of the trigger. It is available during normal
 177         recordings too.
 178
 179   \item[Start Above]
 180         The start threshold defines the minimal volume a sound must have to start the
 181         recording. It is displayed numerically in the line "Start Above". Note that
 182         the unit of the threshold depends on the settings of the peak meter. (i.e.
 183         When the peak meter displays db you can adjust the level in db and when the
 184         peak meter is set to linear the threshold is displayed as percentage.) In the
 185         peak meter at the bottom of the screen the start threshold is displayed
 186         graphically by a little triangle pointing to the right. There are two special
 187         values. The value \setting{Off} turns the start condition off.  With this
 188         setting you have to start the recording manually and the trigger only stops
 189         the recording according to the stop condition. The setting \setting{-inf}
 190         sets the trigger to the absolute minimum. This setting only makes sense when
 191         you record via a digital input as even the noise of the device itself would
 192         exceed this threshold immediately.
 193
 194   \item[for at least]
 195         The start duration defines the minimal duration that a signal must exceed the
 196         start threshold to start the recording. Depending on your situation you may
 197         want to set this setting to 0 (e.g. when copying a song from a commercial
 198         medium) or to quite big values. Because sound is not continuous by nature
 199         (think of percussion) neglectable dropouts are tolerated during this start
 200         duration.
 201
 202   \item[Stop Below]
 203         When the sound level drops below the stop threshold the recording is stopped.
 204         It is displayed numerically in the line "Stop Below". Just like the start
 205         threshold the unit of the stop threshold depends on the settings of the peak
 206         meter. There's also a small triangular marker in the peak meter at the bottom
 207         of the screen. In contrast to the start threshold marker it points to the
 208         left. The value \setting{Off} turns the stop condition off. With this setting you
 209         have to stop the recording manually.
 210
 211   \item[for at least]
 212     This time specifies the duration the signal must drop below the stop
 213         threshold to stop the recording. By selecting high values you can ensure
 214         that, for example, trailing fade-outs are recorded entirely.
 215
 216   \item[Presplit Gap]
 217     When the signal drops below the stop threshold for the time specified by the
 218         presplit gap a new recording may be started when the signal raises above the
 219         start threshold. Thus the value of the presplit gap should be smaller than
 220         the stop hold time. Otherwise the recording would stop anyway and the
 221         presplit gap has no effect. For most uses I recommend to set this parameter
 222         equal to the stop hold time. Sometimes you may encounter a sound source (e.g.
 223         a CD) where the songs have fade outs and hardly any gaps between the tracks.
 224         Here you can set the stop hold time to long values to ensure that all fade
 225         outs are recorded completely. By specifying a short presplit gap you still
 226         can split the recording into seperate tracks whenever the trigger start
 227         condition is met.
 228
 229   \end{description}
 230
 231 More information can be found at \wikilink{VolumeTriggeredRecording}.
 232
 233 \opt{h100,h300}{%
 234   \section{Automatic Gain Control}
 235     The \setting{Automatic Gain Control} has five different presets for
 236     automatically controlling the gain while recording.
 237     \begin{description}
 238       \item[Safety (clip):]
 239         This preset will lower the gain when the levels get too high (-1dB)
 240         and will never increase gain.
 241
 242       \item[Live (slow):]
 243         This preset is designed to be used for recording of live shows and has
 244         quite large headroom for loud parts. It heads for a nominal target peak
 245         level of -9dB and will slowly increase or decrease gain to reach it.
 246
 247       \item[DJ-Set (slow):]
 248         This preset heads for a nominal target peak level of -5dB and will
 249         slowly increase or decrease gain to reach it.
 250
 251       \item[Medium:]
 252         This preset heads for a nominal target peak level of -6dB and will
 253         increase or decrease gain to reach it.
 254
 255       \item[Voice (fast):]
 256         This preset is designed to be used for voice recording and heads for a
 257         nominal target peak level of -7dB and will quickly increase or
 258         decrease gain to reach it.
 259     \end{description}
 260
 261   \section{AGC clip time}
 262     This setting controls how long the level is too loud or soft before the
 263     \setting{Automatic Gain Control} kicks in.
 264 }%
 265
 266