Lansing a écrit:Je ne discuterai pas des histoires de upsampling
et pourquoi donc pas ?
d'apres les jolis diagrammes de son PDF, et mes oreilles en tete de choux-fleur......il semblerait qu'un surechantillonnage 24/96(oversampling donc) permette de "recreer"(avec plus ou moins de brio ) les informations qui n'ont pas ete enregistrees a cause de la reso reduite 16/44.1.
il suffit de comparer les 2 modes de qualite les plus hauts de SRC pour entendre que le plus haut "lisse" les formes d'onde, les rend moins metalliques, plus naturelles que les autres ?!
a la maniere d'un sharpen intelligent pour la video..
SRC_SINC_BEST_QUALITY - This is a bandlimited interpolator derived from the mathematical sinc function and this is the highest quality sinc based converter, providing a worst case Signal-to-Noise Ratio (SNR) of 97 decibels (dB) at a bandwidth of 97%. All three SRC_SINC_* converters are based on the techniques of Julius O. Smith although this code was developed independantly.
SRC_SINC_MEDIUM_QUALITY - This is another bandlimited interpolator much like the previous one. It has an SNR of 97dB and a bandwidth of 90%. The speed of the conversion is much faster than the previous one.
SRC_SINC_FASTEST - This is the fastest bandlimited interpolator and has an SNR of 97dB and a bandwidth of 80%.
SRC_ZERO_ORDER_HOLD - A Zero Order Hold converter (interpolated value is equal to the last value). The quality is poor but the conversion speed is blindlingly fast.
SRC_LINEAR - A linear converter. Again the quality is poor, but the conversion speed is blindingly fast.
apres j'ignore pourquoi il refuse de le faire en temps reel et veut absolument enregistrer du 24/192 surechantillone sur son DD ?!
et reste a s'entendre sur la diff. oversampling/upsampling :
http://www.audioholics.com/education/au ... ital-audio