standard.spg.image: make a bitmap picture of a spectrogram that should look nice...
In landmarkacoustics/SoundPoints-R: an R version of the SoundPoints algorithm

Description Usage Arguments Value Author(s) See Also Examples

makes a black-and-white bitmap with darkness denoting amplitude, with lots of user control over appearance. The output file is in PNG format

1	standard.spg.image(spg, path = "default.png", amplitude.threshold = 0, time.offset = 0, ...)

`spg`	a spectrogram object
`path`	the location of the image file that will be produced
`amplitude.threshold`	any amplitude less than this threshold will be ignored
`time.offset`	you may want to shift the time axis to match up with other files
`...`	further arguments to plot.spg

none

Benjamin N. Taft ben.taft@landmarkacoustics.com

plot.spg png

##---- Should be DIRECTLY executable !! ----
##-- ==>  Define data, use random,
##--	or do  help(data=index)  for the standard data sets.

## The function is currently defined as
function (spg, path = "default.png", amplitude.threshold = 0, 
    time.offset = 0, ...) 
{
    if (is(spg) == "spg") {
        png(path, 5 * 180, 3 * 180, pointsize = 10, res = 180)
        par(mar = c(10, 10, 2, 2)/3, mgp = 2 * c(3, 1, 0)/3)
        temp <- -spg
        temp[temp > amplitude.threshold] <- amplitude.threshold
        image(attr(spg, "time"), attr(spg, "frequency")/1000, 
            temp, col = gray.colors(512, 0, 1), xlab = "Time (s)", 
            xlim = c(0, 3) + time.offset, ylab = "Frequency (kHz)", 
            ylim = c(0, 10), ...)
        dev.off()
    }
  }