pullup.c

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	for (f = c->first; f && f != c->head; f = f->next) {
		pullup_release_buffer(f->buffer, f->parity);
		f->buffer = 0;
	}
	c->first = c->last = 0;
}








#define F_HAVE_BREAKS 1
#define F_HAVE_AFFINITY 2


#define BREAK_LEFT 1
#define BREAK_RIGHT 2




static int queue_length(struct pullup_field *begin, struct pullup_field *end)
{
	int count = 1;
	struct pullup_field *f;
	
	if (!begin || !end) return 0;
	for (f = begin; f != end; f = f->next) count++;
	return count;
}

static int find_first_break(struct pullup_field *f, int max)
{
	int i;
	for (i = 0; i < max; i++) {
		if (f->breaks & BREAK_RIGHT || f->next->breaks & BREAK_LEFT)
			return i+1;
		f = f->next;
	}
	return 0;
}

static void compute_breaks(struct pullup_context *c, struct pullup_field *f0)
{
	int i;
	struct pullup_field *f1 = f0->next;
	struct pullup_field *f2 = f1->next;
	struct pullup_field *f3 = f2->next;
	int l, max_l=0, max_r=0;
	//struct pullup_field *ff;
	//for (i=0, ff=c->first; ff != f0; i++, ff=ff->next);

	if (f0->flags & F_HAVE_BREAKS) return;
	//printf("\n%d: ", i);
	f0->flags |= F_HAVE_BREAKS;

	/* Special case when fields are 100% identical */
	if (f0->buffer == f2->buffer && f1->buffer != f3->buffer) {
		f2->breaks |= BREAK_RIGHT;
		return;
	}
	if (f0->buffer != f2->buffer && f1->buffer == f3->buffer) {
		f1->breaks |= BREAK_LEFT;
		return;
	}

	for (i = 0; i < c->metric_len; i++) {
		l = f2->diffs[i] - f3->diffs[i];
		if (l > max_l) max_l = l;
		if (-l > max_r) max_r = -l;
	}
	/* Don't get tripped up when differences are mostly quant error */
	//printf("%d %d\n", max_l, max_r);
	if (max_l + max_r < 128) return;
	if (max_l > 4*max_r) f1->breaks |= BREAK_LEFT;
	if (max_r > 4*max_l) f2->breaks |= BREAK_RIGHT;
}

static void compute_affinity(struct pullup_context *c, struct pullup_field *f)
{
	int i;
	int max_l=0, max_r=0, l;
	if (f->flags & F_HAVE_AFFINITY) return;
	f->flags |= F_HAVE_AFFINITY;
	if (f->buffer == f->next->next->buffer) {
		f->affinity = 1;
		f->next->affinity = 0;
		f->next->next->affinity = -1;
		f->next->flags |= F_HAVE_AFFINITY;
		f->next->next->flags |= F_HAVE_AFFINITY;
		return;
	}
	for (i = 0; i < c->metric_len; i++) {
		l = f->comb[i] - f->next->comb[i];
		if (l > max_l) max_l = l;
		if (-l > max_r) max_r = -l;
	}
	if (max_l + max_r < 64) return;
	if (max_r > 2*max_l) f->affinity = -1;
	else if (max_l > 2*max_r) f->affinity = 1;
}

static void foo(struct pullup_context *c)
{
	struct pullup_field *f = c->first;
	int i, n = queue_length(f, c->last);
	for (i = 0; i < n-1; i++) {
		if (i < n-3) compute_breaks(c, f);
		compute_affinity(c, f);
		f = f->next;
	}
}

static int decide_frame_length(struct pullup_context *c)
{
	struct pullup_field *f0 = c->first;
	struct pullup_field *f1 = f0->next;
	struct pullup_field *f2 = f1->next;
	struct pullup_field *f3 = f2->next;
	int l;
	
	if (queue_length(c->first, c->last) < 4) return 0;
	foo(c);

	if (f0->affinity == -1) return 1;

	l = find_first_break(f0, 3);
	if (l == 1 && c->strict_breaks < 0) l = 0;
	
	switch (l) {
	case 1:
		if (c->strict_breaks < 1 && f0->affinity == 1 && f1->affinity == -1)
			return 2;
		else return 1;
	case 2:
		/* FIXME: strictly speaking, f0->prev is no longer valid... :) */
		if (c->strict_pairs
			&& (f0->prev->breaks & BREAK_RIGHT) && (f2->breaks & BREAK_LEFT)
			&& (f0->affinity != 1 || f1->affinity != -1) )
			return 1;
		if (f1->affinity == 1) return 1;
		else return 2;
	case 3:
		if (f2->affinity == 1) return 2;
		else return 3;
	default:
		/* 9 possibilities covered before switch */
		if (f1->affinity == 1) return 1; /* covers 6 */
		else if (f1->affinity == -1) return 2; /* covers 6 */
		else if (f2->affinity == -1) { /* covers 2 */
			if (f0->affinity == 1) return 3;
			else return 1;
		}
		else return 2; /* the remaining 6 */
	}
}


static void print_aff_and_breaks(struct pullup_context *c, struct pullup_field *f)
{
	int i;
	int max_l, max_r, l;
	struct pullup_field *f0 = f;
	const char aff_l[] = "+..", aff_r[] = "..+";
	printf("\naffinity: ");
	for (i = 0; i < 4; i++) {
		printf("%c%d%c", aff_l[1+f->affinity], i, aff_r[1+f->affinity]);
		f = f->next;
	}
	f = f0;
	printf("\nbreaks:   ");
	for (i=0; i<4; i++) {
		printf("%c%d%c", f->breaks & BREAK_LEFT ? '|' : '.', i, f->breaks & BREAK_RIGHT ? '|' : '.');
		f = f->next;
	}
	printf("\n");
}





struct pullup_frame *pullup_get_frame(struct pullup_context *c)
{
	int i;
	struct pullup_frame *fr = c->frame;
	int n = decide_frame_length(c);
	int aff = c->first->next->affinity;

	if (!n) return 0;
	if (fr->lock) return 0;

	if (c->verbose) {
		print_aff_and_breaks(c, c->first);
		printf("duration: %d    \n", n);
	}

	fr->lock++;
	fr->length = n;
	fr->parity = c->first->parity;
	fr->buffer = 0;
	for (i = 0; i < n; i++) {
		/* We cheat and steal the buffer without release+relock */
		fr->ifields[i] = c->first->buffer;
		c->first->buffer = 0;
		c->first = c->first->next;
	}
	
	if (n == 1) {
		fr->ofields[fr->parity] = fr->ifields[0];
		fr->ofields[fr->parity^1] = 0;
	} else if (n == 2) {
		fr->ofields[fr->parity] = fr->ifields[0];
		fr->ofields[fr->parity^1] = fr->ifields[1];
	} else if (n == 3) {
		if (aff == 0)
			aff = (fr->ifields[0] == fr->ifields[1]) ? -1 : 1;
		/* else if (c->verbose) printf("forced aff: %d    \n", aff); */
		fr->ofields[fr->parity] = fr->ifields[1+aff];
		fr->ofields[fr->parity^1] = fr->ifields[1];
	}
	pullup_lock_buffer(fr->ofields[0], 0);
	pullup_lock_buffer(fr->ofields[1], 1);
	
	if (fr->ofields[0] == fr->ofields[1]) {
		fr->buffer = fr->ofields[0];
		pullup_lock_buffer(fr->buffer, 2);
		return fr;
	}
	return fr;
}

static void copy_field(struct pullup_context *c, struct pullup_buffer *dest,
	struct pullup_buffer *src, int parity)
{
	int i, j;
	unsigned char *d, *s;
	for (i = 0; i < c->nplanes; i++) {
		s = src->planes[i] + parity*c->stride[i];
		d = dest->planes[i] + parity*c->stride[i];
		for (j = c->h[i]>>1; j; j--) {
			memcpy(d, s, c->stride[i]);
			s += c->stride[i]<<1;
			d += c->stride[i]<<1;
		}
	}
}

void pullup_pack_frame(struct pullup_context *c, struct pullup_frame *fr)
{
	int i;
	int par = fr->parity;
	if (fr->buffer) return;
	if (fr->length < 2) return; /* FIXME: deal with this */
	for (i = 0; i < 2; i++)
	{
		if (fr->ofields[i]->lock[i^1]) continue;
		fr->buffer = fr->ofields[i];
		pullup_lock_buffer(fr->buffer, 2);
		copy_field(c, fr->buffer, fr->ofields[i^1], i^1);
		return;
	}
	fr->buffer = pullup_get_buffer(c, 2);
	copy_field(c, fr->buffer, fr->ofields[0], 0);
	copy_field(c, fr->buffer, fr->ofields[1], 1);
}

void pullup_release_frame(struct pullup_frame *fr)
{
	int i;
	for (i = 0; i < fr->length; i++)
		pullup_release_buffer(fr->ifields[i], fr->parity ^ (i&1));
	pullup_release_buffer(fr->ofields[0], 0);
	pullup_release_buffer(fr->ofields[1], 1);
	if (fr->buffer) pullup_release_buffer(fr->buffer, 2);
	fr->lock--;
}






struct pullup_context *pullup_alloc_context()
{
	struct pullup_context *c;

	c = calloc(1, sizeof(struct pullup_context));

	return c;
}

void pullup_preinit_context(struct pullup_context *c)
{
	c->bpp = calloc(c->nplanes, sizeof(int));
	c->w = calloc(c->nplanes, sizeof(int));
	c->h = calloc(c->nplanes, sizeof(int));
	c->stride = calloc(c->nplanes, sizeof(int));
	c->background = calloc(c->nplanes, sizeof(int));
}

void pullup_init_context(struct pullup_context *c)
{
	int mp = c->metric_plane;
	if (c->nbuffers < 10) c->nbuffers = 10;
	c->buffers = calloc(c->nbuffers, sizeof (struct pullup_buffer));

	c->metric_w = (c->w[mp] - ((c->junk_left + c->junk_right) << 3)) >> 3;
	c->metric_h = (c->h[mp] - ((c->junk_top + c->junk_bottom) << 1)) >> 3;
	c->metric_offset = c->junk_left*c->bpp[mp] + (c->junk_top<<1)*c->stride[mp];
	c->metric_len = c->metric_w * c->metric_h;
	
	c->head = make_field_queue(c, 8);

	c->frame = calloc(1, sizeof (struct pullup_frame));
	c->frame->ifields = calloc(3, sizeof (struct pullup_buffer *));

	switch(c->format) {
	case PULLUP_FMT_Y:
		c->diff = diff_y;
		c->comb = licomb_y;
#ifdef ARCH_X86
#ifdef HAVE_MMX
		if (c->cpu & PULLUP_CPU_MMX) {
			c->diff = diff_y_mmx;
			c->comb = licomb_y_mmx;
		}
#endif
#endif
		/* c->comb = qpcomb_y; */
		break;
#if 0
	case PULLUP_FMT_YUY2:
		c->diff = diff_yuy2;
		break;
	case PULLUP_FMT_RGB32:
		c->diff = diff_rgb32;
		break;
#endif
	}
}

void pullup_free_context(struct pullup_context *c)
{
	struct pullup_field *f;
	free(c->buffers);
	f = c->head;
	do {
		free(f->diffs);
		free(f->comb);
		f = f->next;
		free(f->prev);
	} while (f != c->head);
	free(c->frame);
	free(c);
}