Convert OVR file from FieldHints to TFM format.

[Dogway]

The output file I get from YATTA is formatted for FieldHints and doesn't seem to work with TFM, which I want to use due to better field matching quality. I'm wondering if there's something I can do since their TFM's ovr format is a bit convoluted IMO:

This is fieldhints format:

0,0,-
1,1,-
2,2,-
4,3,-
5,4,-
5,5,-
6,6,-

It goes frame by frame matching fields, the first figure are "top" fields the second "bottom". The minus is to output as progressive (not interlaced).

TFM's ovr is a bit more complicated, here is a link.
My thought is something like this would work, but I'm not sure how to get from the above to this, even with regex.

0 c
1 c
2 c
4 p
5 p
5 c
6 c

[Brad]

Doesn't your FieldHint file tell the filter which fields to match for every single field in the source?

In that case you wouldn't be using TFM's field-match guessing algorithm even if you converted the format to 'TFM ovr'.

Or are you claiming that the video quality of a "5,4" frame output by FieldHint is somehow worse than a "5 p" from TFM?

[Dogway]

Yes, even for the same field matching FieldHint's quality is a bit worse (jagged, aliased...). I'm trying to port the metrics to TFM readable format.

[Brad]

Apart from TFM being better-optimized (faster), they combine fields the same way.

FieldHint 0.1 frame-drawing algorithm:

PVideoFrame __stdcall FieldHint::GetFrame(int n, IScriptEnvironment* env)
{
   PVideoFrame newframe = env->NewVideoFrame(vi);
    PVideoFrame tf = child->GetFrame(ovr[n].tf, env);
    PVideoFrame bf = child->GetFrame(ovr[n].bf, env);
    CopyField(newframe, tf, 0);
    CopyField(newframe, bf, 1);
[...]
    return newframe;
}

void FieldHint::CopyField(PVideoFrame& to, PVideoFrame& from, int field)
{
    const static int planes[] = {PLANAR_Y, PLANAR_U, PLANAR_V};
    int p;
    for(p = 0; p < (vi.IsYV12() ? 3 : 1); p++)
    {
        env->BitBlt(to->GetWritePtr(planes[p]) + to->GetPitch(planes[p])*field,
                    to->GetPitch(planes[p])*2,
                    from->GetReadPtr(planes[p]) + from->GetPitch(planes[p])*field,
                    from->GetPitch(planes[p])*2,
                    from->GetRowSize(planes[p]),
                    (from->GetHeight(planes[p]) + !field) / 2);
    }
}

TFM 1.0.5 frame-drawing algorithm:

void TFM::createWeaveFrame(PVideoFrame &dst, PVideoFrame &prv, PVideoFrame &src, 
        PVideoFrame &nxt, IScriptEnvironment *env, int match, int &cfrm, int np)
{
    if (cfrm == match)
        return;
    int b, plane;
    for (b=0; b<np; ++b)
    {
        if (b == 0) plane = PLANAR_Y;
        else if (b == 1) plane = PLANAR_V;
        else plane = PLANAR_U;
        if (match == 0)
        {
            env->BitBlt(dst->GetWritePtr(plane)+(1-field)*dst->GetPitch(plane),dst->GetPitch(plane)<<1,
                src->GetReadPtr(plane)+(1-field)*src->GetPitch(plane),src->GetPitch(plane)<<1, 
                src->GetRowSize(plane),src->GetHeight(plane)>>1);
            env->BitBlt(dst->GetWritePtr(plane)+field*dst->GetPitch(plane),dst->GetPitch(plane)<<1, 
                prv->GetReadPtr(plane)+field*prv->GetPitch(plane),prv->GetPitch(plane)<<1, 
                prv->GetRowSize(plane),prv->GetHeight(plane)>>1);
        }
        else if (match == 1)
        {
            env->BitBlt(dst->GetWritePtr(plane),dst->GetPitch(plane),src->GetReadPtr(plane), 
                src->GetPitch(plane),src->GetRowSize(plane),src->GetHeight(plane));
        }
        else if (match == 2)
        {
            env->BitBlt(dst->GetWritePtr(plane)+(1-field)*dst->GetPitch(plane),dst->GetPitch(plane)<<1,
                src->GetReadPtr(plane)+(1-field)*src->GetPitch(plane),src->GetPitch(plane)<<1, 
                src->GetRowSize(plane),src->GetHeight(plane)>>1);
            env->BitBlt(dst->GetWritePtr(plane)+field*dst->GetPitch(plane),dst->GetPitch(plane)<<1, 
                nxt->GetReadPtr(plane)+field*nxt->GetPitch(plane),nxt->GetPitch(plane)<<1,
                nxt->GetRowSize(plane),nxt->GetHeight(plane)>>1);
        }
        else if (match == 3)
        {
            env->BitBlt(dst->GetWritePtr(plane)+field*dst->GetPitch(plane),dst->GetPitch(plane)<<1,
                src->GetReadPtr(plane)+field*src->GetPitch(plane),src->GetPitch(plane)<<1, 
                src->GetRowSize(plane),src->GetHeight(plane)>>1);
            env->BitBlt(dst->GetWritePtr(plane)+(1-field)*dst->GetPitch(plane),dst->GetPitch(plane)<<1, 
                prv->GetReadPtr(plane)+(1-field)*prv->GetPitch(plane),prv->GetPitch(plane)<<1, 
                prv->GetRowSize(plane),prv->GetHeight(plane)>>1);
        }
        else if (match == 4)
        {
            env->BitBlt(dst->GetWritePtr(plane)+field*dst->GetPitch(plane),dst->GetPitch(plane)<<1,
                src->GetReadPtr(plane)+field*src->GetPitch(plane),src->GetPitch(plane)<<1, 
                src->GetRowSize(plane),src->GetHeight(plane)>>1);
            env->BitBlt(dst->GetWritePtr(plane)+(1-field)*dst->GetPitch(plane),dst->GetPitch(plane)<<1, 
                nxt->GetReadPtr(plane)+(1-field)*nxt->GetPitch(plane),nxt->GetPitch(plane)<<1, 
                nxt->GetRowSize(plane),nxt->GetHeight(plane)>>1);
        }
        else env->ThrowError("TFM:  an unknown error occurred (no such match!)");
    }
    cfrm = match;
}

[Dogway]

I threw a ShowFrameNumbers() to see what was happening, I think it was just a different fieldmatching, probably a wrong fieldmatching on the jagged/aliased frame.

Sometimes fieldmatching quality is not perfect and comparisons side to side with TFM can reveal this, what I might be overlooked is that this makes up for correct fieldmatching on the long run, further seeking I can see a wrong fieldmatching in the TFM that is not present in FieldHints, so as you showed I'm sure I would get exact results in case TFM were doing the right thing.

I was almost to drop YATTA for this project seeing that all the decimations were correct, I overlooked fieldmatching accuracy completely. Thanks for confirming the source.