Wei Liu

When skip_precursor is turned on, the adjoint/backward problem is not solved all the way down to time zero. That could be the explanation for the failure to reproduce the reference...

The code shall pass all tests with skip_precursor off. Is that the case? Since the reference data for gradtest and hesstest assume time zero, the option with skip_precursor on shall...

The gradient is cut within t0 before reaching zero because the cross-correlation contribution is confined very locally to the source and shall have little effect on velocity perturbation. It is...

The original design was lossy to save compute time when the gradient is spatially localized to the source. The new revision (less aggressive) removes such a time stepping truncation by...

The main cutoff criterion is the minimum propagation time (t_trunc) from source to the sides based on the velocity model. The main motivation is to save memory storage for high...

The frequency-dependent precursor will still take the minimum propagation time (t_trunc based on the velocity model) to reach boundaries, so the saving on recording before t_trunc ought to not affect...