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