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View Full Version : a few very tricky lossy or lossless spec images


vold911
2012-01-15, 06:39 AM
all of these are audience tapes from early 80s
especially curious about the first one as i cant see the lego skyline or any big black pacthes except complete blackness above the 16k line
the other images also have very distinct flat lines at varying places though all of them seem to lack the lego blocks

http://img341.imageshack.us/img341/1432/830915.jpg (http://imageshack.us/photo/my-images/341/830915.jpg/)

http://img804.imageshack.us/img804/1184/830915rm.jpg (http://imageshack.us/photo/my-images/804/830915rm.jpg/)

http://img402.imageshack.us/img402/9886/840304.jpg (http://imageshack.us/photo/my-images/402/840304.jpg/)

http://img209.imageshack.us/img209/6826/840217.jpg (http://imageshack.us/photo/my-images/209/840217.jpg/)

http://img3.imageshack.us/img3/5705/8208271.jpg (http://imageshack.us/photo/my-images/3/8208271.jpg/)

AAR.oner
2012-01-15, 06:55 AM
most of these look like fairly typical cassette source spectrums

the "flat lines" you refer to are common to analogue broadcast sources...called the pilot tone, they occur at ~16-17kHz for TV sources, and FM's pilot tone runs ~19kHz...they can also be created during transfer, caused by electrical hum/gear, and appear pretty much anywhere in the spectrum

vold911
2012-01-15, 09:06 AM
most of these look like fairly typical cassette source spectrums

the "flat lines" you refer to are common to analogue broadcast sources...called the pilot tone, they occur at ~16-17kHz for TV sources, and FM's pilot tone runs ~19kHz...they can also be created during transfer, caused by electrical hum/gear, and appear pretty much anywhere in the spectrum

so they are all lossless?

tonebloke
2012-01-15, 10:09 PM
Thanks for that explanation AAR.oner. Very useful,


so they are all lossless?

I would call the first SA lossy.

bertrand
2012-01-25, 11:54 PM
First one is a terrible mp3, the others I would need FFT1024 cool edit videos or an audio sample.