[PATCH v1] media: vivid: Extend FPS rates offered by simulated webcam
From: Max Staudt
Date: Fri Apr 14 2023 - 03:24:45 EST
This adds an option for higher frame rates from a simulated webcam.
Currently, vivid emulates (amongst other things) a webcam with somewhat
limited bandwidth - higher resolutions deliver fewer frames per second.
$ yavta --enum-formats -c /dev/video0
Device /dev/video0 opened.
Device `vivid' on `platform:vivid-000' (driver 'vivid') supports video, capture, without mplanes.
- Available formats:
Format 0: YUYV (56595559)
Type: Video capture (1)
Name: YUYV 4:2:2
Frame size: 320x180 (1/1, 1/2, 1/4, 1/5, 1/10, 2/25, 1/15, 1/25, 1/30, 1/40, 1/50, 1/60)
Frame size: 640x360 (1/1, 1/2, 1/4, 1/5, 1/10, 2/25, 1/15, 1/25, 1/30, 1/40)
Frame size: 640x480 (1/1, 1/2, 1/4, 1/5, 1/10, 2/25, 1/15, 1/25)
Frame size: 1280x720 (1/1, 1/2, 1/4, 1/5, 1/10, 2/25)
Frame size: 1920x1080 (1/1, 1/2, 1/4, 1/5)
Frame size: 3840x2160 (1/1, 1/2)
In some test cases, it is useful to allow for higher frame rates, as
configurations such as 720p@30 FPS have become commonplace now.
This patch allows:
0- 719p - 120fps
720-1079p - 60fps
1080-2159p - 30fps
2160p - 15fps
$ yavta --enum-formats -c /dev/video0
Device /dev/video0 opened.
Device `vivid' on `platform:vivid-000' (driver 'vivid') supports video, capture, without mplanes.
- Available formats:
Format 0: YUYV (56595559)
Type: Video capture (1)
Name: YUYV 4:2:2
Frame size: 320x180 (1/1, 1/2, 1/4, 1/5, 1/10, 2/25, 1/15, 1/25, 1/30, 1/40, 1/50, 1/60, 1/120)
Frame size: 640x360 (1/1, 1/2, 1/4, 1/5, 1/10, 2/25, 1/15, 1/25, 1/30, 1/40, 1/50, 1/60, 1/120)
Frame size: 640x480 (1/1, 1/2, 1/4, 1/5, 1/10, 2/25, 1/15, 1/25, 1/30, 1/40, 1/50, 1/60, 1/120)
Frame size: 1280x720 (1/1, 1/2, 1/4, 1/5, 1/10, 2/25, 1/15, 1/25, 1/30, 1/40, 1/50, 1/60)
Frame size: 1920x1080 (1/1, 1/2, 1/4, 1/5, 1/10, 2/25, 1/15, 1/25, 1/30)
Frame size: 3840x2160 (1/1, 1/2, 1/4, 1/5, 1/10, 2/25, 1/15)
Passes: v4l2-compliance 1.25.0-5039 from v4l-utils git ccc08732823f
Signed-off-by: Max Staudt <mstaudt@xxxxxxxxxxxx>
---
.../media/test-drivers/vivid/vivid-vid-cap.c | 49 +++++++++++++------
1 file changed, 34 insertions(+), 15 deletions(-)
diff --git a/drivers/media/test-drivers/vivid/vivid-vid-cap.c b/drivers/media/test-drivers/vivid/vivid-vid-cap.c
index c0999581c599..27214f5f0811 100644
--- a/drivers/media/test-drivers/vivid/vivid-vid-cap.c
+++ b/drivers/media/test-drivers/vivid/vivid-vid-cap.c
@@ -45,13 +45,8 @@ static const struct vivid_fmt formats_ovl[] = {
},
};
-/* The number of discrete webcam framesizes */
-#define VIVID_WEBCAM_SIZES 6
-/* The number of discrete webcam frameintervals */
-#define VIVID_WEBCAM_IVALS (VIVID_WEBCAM_SIZES * 2)
-
/* Sizes must be in increasing order */
-static const struct v4l2_frmsize_discrete webcam_sizes[VIVID_WEBCAM_SIZES] = {
+static const struct v4l2_frmsize_discrete webcam_sizes[] = {
{ 320, 180 },
{ 640, 360 },
{ 640, 480 },
@@ -64,21 +59,43 @@ static const struct v4l2_frmsize_discrete webcam_sizes[VIVID_WEBCAM_SIZES] = {
* Intervals must be in increasing order and there must be twice as many
* elements in this array as there are in webcam_sizes.
*/
-static const struct v4l2_fract webcam_intervals[VIVID_WEBCAM_IVALS] = {
+static const struct v4l2_fract webcam_intervals[] = {
{ 1, 1 },
{ 1, 2 },
{ 1, 4 },
{ 1, 5 },
{ 1, 10 },
{ 2, 25 },
- { 1, 15 },
+ { 1, 15 }, /* 7 - maximum for 2160p */
{ 1, 25 },
- { 1, 30 },
+ { 1, 30 }, /* 9 - maximum for 1080p */
{ 1, 40 },
{ 1, 50 },
- { 1, 60 },
+ { 1, 60 }, /* 12 - maximum for 720p */
+ { 1, 120 },
};
+/* Limit maximum FPS rates for high resolutions */
+#define IVAL_COUNT_720P 12 /* 720p and up is limited to 60 fps */
+#define IVAL_COUNT_1080P 9 /* 1080p and up is limited to 30 fps */
+#define IVAL_COUNT_2160P 7 /* 2160p and up is limited to 15 fps */
+
+static inline unsigned webcam_ival_count(const struct vivid_dev *dev,
+ unsigned frmsize_idx)
+{
+ if (webcam_sizes[frmsize_idx].height >= 2160)
+ return IVAL_COUNT_2160P;
+
+ if (webcam_sizes[frmsize_idx].height >= 1080)
+ return IVAL_COUNT_1080P;
+
+ if (webcam_sizes[frmsize_idx].height >= 720)
+ return IVAL_COUNT_720P;
+
+ /* For low resolutions, allow all FPS rates */
+ return ARRAY_SIZE(webcam_intervals);
+}
+
static int vid_cap_queue_setup(struct vb2_queue *vq,
unsigned *nbuffers, unsigned *nplanes,
unsigned sizes[], struct device *alloc_devs[])
@@ -592,7 +609,7 @@ int vivid_try_fmt_vid_cap(struct file *file, void *priv,
if (vivid_is_webcam(dev)) {
const struct v4l2_frmsize_discrete *sz =
v4l2_find_nearest_size(webcam_sizes,
- VIVID_WEBCAM_SIZES, width,
+ ARRAY_SIZE(webcam_sizes), width,
height, mp->width, mp->height);
w = sz->width;
@@ -773,14 +790,16 @@ int vivid_s_fmt_vid_cap(struct file *file, void *priv,
compose->height /= factor;
}
} else if (vivid_is_webcam(dev)) {
+ unsigned ival_sz = webcam_ival_count(dev, dev->webcam_size_idx);
+
/* Guaranteed to be a match */
for (i = 0; i < ARRAY_SIZE(webcam_sizes); i++)
if (webcam_sizes[i].width == mp->width &&
webcam_sizes[i].height == mp->height)
break;
dev->webcam_size_idx = i;
- if (dev->webcam_ival_idx >= 2 * (VIVID_WEBCAM_SIZES - i))
- dev->webcam_ival_idx = 2 * (VIVID_WEBCAM_SIZES - i) - 1;
+ if (dev->webcam_ival_idx >= ival_sz)
+ dev->webcam_ival_idx = ival_sz - 1;
vivid_update_format_cap(dev, false);
} else {
struct v4l2_rect r = { 0, 0, mp->width, mp->height };
@@ -1908,7 +1927,7 @@ int vidioc_enum_frameintervals(struct file *file, void *priv,
break;
if (i == ARRAY_SIZE(webcam_sizes))
return -EINVAL;
- if (fival->index >= 2 * (VIVID_WEBCAM_SIZES - i))
+ if (fival->index >= webcam_ival_count(dev, i))
return -EINVAL;
fival->type = V4L2_FRMIVAL_TYPE_DISCRETE;
fival->discrete = webcam_intervals[fival->index];
@@ -1935,7 +1954,7 @@ int vivid_vid_cap_s_parm(struct file *file, void *priv,
struct v4l2_streamparm *parm)
{
struct vivid_dev *dev = video_drvdata(file);
- unsigned ival_sz = 2 * (VIVID_WEBCAM_SIZES - dev->webcam_size_idx);
+ unsigned ival_sz = webcam_ival_count(dev, dev->webcam_size_idx);
struct v4l2_fract tpf;
unsigned i;
--
2.40.0.634.g4ca3ef3211-goog