[FFmpeg-cvslog] avfilter/vf_v360: allow user to control fov for equirectagular format
Paul B Mahol
git at videolan.org
Sun Apr 11 02:04:18 EEST 2021
ffmpeg | branch: master | Paul B Mahol <onemda at gmail.com> | Sun Apr 11 00:56:44 2021 +0200| [1050f94c229d4b157467f94de367f87499706c0d] | committer: Paul B Mahol
avfilter/vf_v360: allow user to control fov for equirectagular format
It may be useful to use different values from typical 360/180 deg.
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=1050f94c229d4b157467f94de367f87499706c0d
---
libavfilter/vf_v360.c | 114 +++++++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 103 insertions(+), 11 deletions(-)
diff --git a/libavfilter/vf_v360.c b/libavfilter/vf_v360.c
index 94473cd5b3..87105dbe92 100644
--- a/libavfilter/vf_v360.c
+++ b/libavfilter/vf_v360.c
@@ -148,8 +148,8 @@ static const AVOption v360_options[] = {
{ "pitch", "pitch rotation", OFFSET(pitch), AV_OPT_TYPE_FLOAT, {.dbl=0.f}, -180.f, 180.f,TFLAGS, "pitch"},
{ "roll", "roll rotation", OFFSET(roll), AV_OPT_TYPE_FLOAT, {.dbl=0.f}, -180.f, 180.f,TFLAGS, "roll"},
{ "rorder", "rotation order", OFFSET(rorder), AV_OPT_TYPE_STRING, {.str="ypr"}, 0, 0,TFLAGS, "rorder"},
- { "h_fov", "output horizontal field of view",OFFSET(h_fov), AV_OPT_TYPE_FLOAT, {.dbl=90.f}, 0.00001f, 360.f,TFLAGS, "h_fov"},
- { "v_fov", "output vertical field of view", OFFSET(v_fov), AV_OPT_TYPE_FLOAT, {.dbl=45.f}, 0.00001f, 360.f,TFLAGS, "v_fov"},
+ { "h_fov", "output horizontal field of view",OFFSET(h_fov), AV_OPT_TYPE_FLOAT, {.dbl=0.f}, 0.f, 360.f,TFLAGS, "h_fov"},
+ { "v_fov", "output vertical field of view", OFFSET(v_fov), AV_OPT_TYPE_FLOAT, {.dbl=0.f}, 0.f, 360.f,TFLAGS, "v_fov"},
{ "d_fov", "output diagonal field of view", OFFSET(d_fov), AV_OPT_TYPE_FLOAT, {.dbl=0.f}, 0.f, 360.f,TFLAGS, "d_fov"},
{ "h_flip", "flip out video horizontally", OFFSET(h_flip), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1,TFLAGS, "h_flip"},
{ "v_flip", "flip out video vertically", OFFSET(v_flip), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1,TFLAGS, "v_flip"},
@@ -158,8 +158,8 @@ static const AVOption v360_options[] = {
{ "iv_flip", "flip in video vertically", OFFSET(iv_flip), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1,TFLAGS, "iv_flip"},
{ "in_trans", "transpose video input", OFFSET(in_transpose), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, FLAGS, "in_transpose"},
{ "out_trans", "transpose video output", OFFSET(out_transpose), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, FLAGS, "out_transpose"},
- { "ih_fov", "input horizontal field of view",OFFSET(ih_fov), AV_OPT_TYPE_FLOAT, {.dbl=90.f}, 0.00001f, 360.f,TFLAGS, "ih_fov"},
- { "iv_fov", "input vertical field of view", OFFSET(iv_fov), AV_OPT_TYPE_FLOAT, {.dbl=45.f}, 0.00001f, 360.f,TFLAGS, "iv_fov"},
+ { "ih_fov", "input horizontal field of view",OFFSET(ih_fov), AV_OPT_TYPE_FLOAT, {.dbl=0.f}, 0.f, 360.f,TFLAGS, "ih_fov"},
+ { "iv_fov", "input vertical field of view", OFFSET(iv_fov), AV_OPT_TYPE_FLOAT, {.dbl=0.f}, 0.f, 360.f,TFLAGS, "iv_fov"},
{ "id_fov", "input diagonal field of view", OFFSET(id_fov), AV_OPT_TYPE_FLOAT, {.dbl=0.f}, 0.f, 360.f,TFLAGS, "id_fov"},
{"alpha_mask", "build mask in alpha plane", OFFSET(alpha), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, FLAGS, "alpha"},
{ NULL }
@@ -1728,6 +1728,23 @@ static int xyz_to_cube6x1(const V360Context *s,
return 1;
}
+/**
+ * Prepare data for processing equirectangular output format.
+ *
+ * @param ctx filter context
+ *
+ * @return error code
+ */
+static int prepare_equirect_out(AVFilterContext *ctx)
+{
+ V360Context *s = ctx->priv;
+
+ s->flat_range[0] = s->h_fov * M_PI / 360.f;
+ s->flat_range[1] = s->v_fov * M_PI / 360.f;
+
+ return 0;
+}
+
/**
* Calculate 3D coordinates on sphere for corresponding frame position in equirectangular format.
*
@@ -1742,8 +1759,8 @@ static int equirect_to_xyz(const V360Context *s,
int i, int j, int width, int height,
float *vec)
{
- const float phi = ((2.f * i + 0.5f) / width - 1.f) * M_PI;
- const float theta = ((2.f * j + 0.5f) / height - 1.f) * M_PI_2;
+ const float phi = ((2.f * i + 0.5f) / width - 1.f) * s->flat_range[0];
+ const float theta = ((2.f * j + 0.5f) / height - 1.f) * s->flat_range[1];
const float sin_phi = sinf(phi);
const float cos_phi = cosf(phi);
@@ -2103,6 +2120,23 @@ static int xyz_to_orthographic(const V360Context *s,
return visible;
}
+/**
+ * Prepare data for processing equirectangular input format.
+ *
+ * @param ctx filter context
+ *
+ * @return error code
+ */
+static int prepare_equirect_in(AVFilterContext *ctx)
+{
+ V360Context *s = ctx->priv;
+
+ s->iflat_range[0] = s->ih_fov * M_PI / 360.f;
+ s->iflat_range[1] = s->iv_fov * M_PI / 360.f;
+
+ return 0;
+}
+
/**
* Calculate frame position in equirectangular format for corresponding 3D coordinates on sphere.
*
@@ -2122,15 +2156,18 @@ static int xyz_to_equirect(const V360Context *s,
const float phi = atan2f(vec[0], vec[2]);
const float theta = asinf(vec[1]);
- const float uf = (phi / M_PI + 1.f) * width / 2.f;
- const float vf = (theta / M_PI_2 + 1.f) * height / 2.f;
+ const float uf = (phi / s->iflat_range[0] + 1.f) * width / 2.f;
+ const float vf = (theta / s->iflat_range[1] + 1.f) * height / 2.f;
const int ui = floorf(uf);
const int vi = floorf(vf);
+ int visible;
*du = uf - ui;
*dv = vf - vi;
+ visible = vi >= 0 && vi < height && ui >= 0 && ui < width;
+
for (int i = 0; i < 4; i++) {
for (int j = 0; j < 4; j++) {
us[i][j] = ereflectx(ui + j - 1, vi + i - 1, width, height);
@@ -2138,7 +2175,7 @@ static int xyz_to_equirect(const V360Context *s,
}
}
- return 1;
+ return visible;
}
/**
@@ -4003,6 +4040,10 @@ static int allocate_plane(V360Context *s, int sizeof_uv, int sizeof_ker, int siz
static void fov_from_dfov(int format, float d_fov, float w, float h, float *h_fov, float *v_fov)
{
switch (format) {
+ case EQUIRECTANGULAR:
+ *h_fov = d_fov;
+ *v_fov = d_fov * 0.5f;
+ break;
case ORTHOGRAPHIC:
{
const float d = 0.5f * hypotf(w, h);
@@ -4145,6 +4186,10 @@ static int config_output(AVFilterLink *outlink)
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
const int depth = desc->comp[0].depth;
const int sizeof_mask = s->mask_size = (depth + 7) >> 3;
+ float default_h_fov = 360.f;
+ float default_v_fov = 180.f;
+ float default_ih_fov = 360.f;
+ float default_iv_fov = 180.f;
int sizeof_uv;
int sizeof_ker;
int err;
@@ -4274,6 +4319,29 @@ static int config_output(AVFilterLink *outlink)
s->in_width = s->inplanewidth[0];
s->in_height = s->inplaneheight[0];
+ switch (s->in) {
+ case CYLINDRICAL:
+ case FLAT:
+ default_ih_fov = 90.f;
+ default_iv_fov = 45.f;
+ break;
+ case EQUISOLID:
+ case ORTHOGRAPHIC:
+ case STEREOGRAPHIC:
+ case DUAL_FISHEYE:
+ case FISHEYE:
+ default_ih_fov = 180.f;
+ default_iv_fov = 180.f;
+ default:
+ break;
+ }
+
+ if (s->ih_fov == 0.f)
+ s->ih_fov = default_ih_fov;
+
+ if (s->iv_fov == 0.f)
+ s->iv_fov = default_iv_fov;
+
if (s->id_fov > 0.f)
fov_from_dfov(s->in, s->id_fov, w, h, &s->ih_fov, &s->iv_fov);
@@ -4283,7 +4351,7 @@ static int config_output(AVFilterLink *outlink)
switch (s->in) {
case EQUIRECTANGULAR:
s->in_transform = xyz_to_equirect;
- err = 0;
+ err = prepare_equirect_in(ctx);
wf = w;
hf = h;
break;
@@ -4434,7 +4502,7 @@ static int config_output(AVFilterLink *outlink)
switch (s->out) {
case EQUIRECTANGULAR:
s->out_transform = equirect_to_xyz;
- prepare_out = NULL;
+ prepare_out = prepare_equirect_out;
w = lrintf(wf);
h = lrintf(hf);
break;
@@ -4607,6 +4675,30 @@ static int config_output(AVFilterLink *outlink)
s->width = w;
s->height = h;
+ switch (s->out) {
+ case CYLINDRICAL:
+ case FLAT:
+ default_h_fov = 90.f;
+ default_v_fov = 45.f;
+ break;
+ case EQUISOLID:
+ case ORTHOGRAPHIC:
+ case STEREOGRAPHIC:
+ case DUAL_FISHEYE:
+ case FISHEYE:
+ default_h_fov = 180.f;
+ default_v_fov = 180.f;
+ break;
+ default:
+ break;
+ }
+
+ if (s->h_fov == 0.f)
+ s->h_fov = default_h_fov;
+
+ if (s->v_fov == 0.f)
+ s->v_fov = default_v_fov;
+
if (s->d_fov > 0.f)
fov_from_dfov(s->out, s->d_fov, w, h, &s->h_fov, &s->v_fov);
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