[MEncoder-users] turbo

[Guillaume POIRIER]

Hello,

On Mon, Jul 28, 2008 at 8:47 PM, tripp <eliared at yahoo.com> wrote:
> hi,
>
>
> i'm interested in knowing exactly what turbo changes on the first pass, (lavc)
> i know it disables trellis, but what else?

Read the fine source, in libmpcodecs/ve_lavc.c:

        if(lavc_param_turbo && (lavc_param_vpass == 1)) {
          /* uses SAD comparison functions instead of other hungrier */
          lavc_venc_context->me_pre_cmp = 0;
          lavc_venc_context->me_cmp = 0;
          lavc_venc_context->me_sub_cmp = 0;
          lavc_venc_context->mb_cmp = 2;

          /* Disables diamond motion estimation */
          lavc_venc_context->pre_dia_size = 0;
          lavc_venc_context->dia_size = 1;

          lavc_venc_context->quantizer_noise_shaping = 0; // qns=0
          lavc_venc_context->noise_reduction = 0; // nr=0
          lavc_venc_context->mb_decision = 0; // mbd=0 ("realtime" encoding)

          lavc_venc_context->flags &= ~CODEC_FLAG_QPEL;
          lavc_venc_context->flags &= ~CODEC_FLAG_4MV;
          lavc_venc_context->flags &= ~CODEC_FLAG_TRELLIS_QUANT;
          lavc_venc_context->flags &= ~CODEC_FLAG_CBP_RD;
          lavc_venc_context->flags &= ~CODEC_FLAG_QP_RD;
          lavc_venc_context->flags &= ~CODEC_FLAG_MV0;
        }
        break;


-- 
I don't measure a man's success by how high he climbs but how high he
bounces when he hits bottom.
 -- George S. Patton