[Ffmpeg-devel] [PATCH] tunable vb_strategy=1

[Jeff Clagg]

On Mon, May 29, 2006 at 06:47:11PM -0700, Corey Hickey wrote:
> vb_strategy=1:b_sensitivity=n
>  n   psnr  %I  %P  %B      q    qI    qP    qB    t1   t2
> ---------------------------------------------------------
>  1  42.95   2  31  66   4.75  2.89  3.18  5.55   228  387
>  5  42.92   2  41  56   4.74  3.15  3.44  5.74   218  363
> 10  42.90   1  47  50   4.71  3.35  3.61  5.81   213  350
> 15  42.88   1  51  47   4.70  3.26  3.68  5.86   211  344
> 20  42.86   1  53  44   4.68  3.44  3.73  5.88   210  340
> 25  42.85   1  55  42   4.66  3.31  3.76  5.88   208  336
> 30  42.84   1  56  41   4.65  3.35  3.79  5.90   207  335
> 35  42.84   1  58  39   4.63  3.42  3.80  5.89   206  332
> 40  42.83   2  58  39   4.63  3.38  3.82  5.91   206  338  *default*
> 45  42.82   1  60  37   4.62  3.37  3.84  5.92   209  336
> 50  42.82   2  61  36   4.60  3.52  3.86  5.92   209  332
> 55  42.82   2  61  36   4.60  3.52  3.87  5.91   208  334
> 60  42.82   2  62  35   4.60  3.56  3.88  5.92   208  334
> 65  42.81   2  63  34   4.59  3.44  3.89  5.92   207  327
> 70  42.81   2  63  34   4.58  3.67  3.90  5.92   204  326
> 75  42.81   2  63  34   4.58  3.67  3.90  5.92   204  324
> 80  42.80   2  64  33   4.58  3.57  3.92  5.92   204  322

I get the idea this is sort of a low motion clip you're testing with
here. Did you verify that you don't get excessive B-frames, and a PSNR
drop, when lowering n on a higher motion clip?