1. A method comprising: obtaining a target distortion and a transformed signal, the target distortion indicating desired signal quality, and the transformed signal comprising sub-components resulting from a source signal being transformed by a multi-resolution decomposition; distributing the target distortion among the sub-components to produce target sub-component distortions; determining quantizer values for the sub-components based on the target sub-component distortions; and quantizing the sub-components with the determined quantizer values; wherein the distributing, the determining and the quantizing are performed using one or more processors; wherein the sub-components comprise sub-bands resulting from the source signal being transformed by a wavelet-based, frequency-dependent, multi-resolution decomposition, the target sub-component distortions comprise target sub-band distortions, and distributing the target distortion comprises distributing the target distortion among the sub-bands based on energy weights of the sub-bands; the method further comprising ascertaining actual sub-band distortion values that result at different grades of quantization in a current sub-band, wherein determining quantizer values comprises: if a target sub-band distortion for the current sub-band falls between at least two of the actual sub-band distortion values determined for the current sub-band, interpolating between at least two of the quantization grades based on the at least two actual sub-band distortion values to determine a quantizer value for the current sub-band corresponding to the target sub-band distortion for the current sub-band; and wherein distributing the target distortion comprises distributing the target distortion among the sub-bands in inverse proportion to the energy weights of the sub-bands, and determining quantizer values further comprises: determining quantizer values for the sub-bands starting at a highest resolution level and ending at a lowest resolution level of the sub-bands, and if one or more sub-bands of a current resolution level cannot satisfy one or more corresponding target sub-band distortions, redistributing an unsatisfied portion of the one or more corresponding target sub-band distortions to target sub-band distortions for lower resolution sub-bands in inverse proportion to energy weights of the lower resolution sub-bands.