Notes about making aravis work with the FLIR Boson USB camera

[dkogan]

Hi. I'm using aravis with the FLIR Boson now. It works with a few modifications, described here.

This is a USB3 camera; it does v4l2, not genicam. That is supported by aravis. I'm using a recent HEAD from git: 6c5ed99. This camera uses the mono16 pixel format. At this time aravis-v4l2 only supports yuv422, so I had to tell aravis about mono16:

diff --git a/src/arvv4l2misc.c b/src/arvv4l2misc.c
index f9dcdc0e..e79ac66d 100644
--- a/src/arvv4l2misc.c
+++ b/src/arvv4l2misc.c
@@ -16,6 +16,7 @@ typedef struct {
 
 static ArvV4l2GenicamPixelFormat pixel_format_map[] = {
         {V4L2_PIX_FMT_YUYV,             ARV_PIXEL_FORMAT_YUV_422_YUYV_PACKED},
+        {V4L2_PIX_FMT_Y16,              ARV_PIXEL_FORMAT_MONO_16},
 /* Disable these formats for now, makes gstreamer crash:
         {V4L2_PIX_FMT_RGB24,            ARV_PIXEL_FORMAT_RGB_8_PACKED},
         {V4L2_PIX_FMT_BGR24,            ARV_PIXEL_FORMAT_BGR_8_PACKED},

That mostly makes it work. Unideal things:

• arv_camera_dup_available_pixel_formats_as_strings() says this pixel format is called "16-bit Greyscale", instead of "mono16" (or something like that) for normal genicam cameras. So calling arv_camera_set_pixel_format(...,ARV_PIXEL_FORMAT_MONO_16,...) doesn't work: [PixelFormat] [PixelFormatRegister] Invalid address (0x00000128). This format is set by default, however, so the workaround is to simply not try to set it
• Similarly, trying to set the width or height doesn't work. But they're correct to begin with, and we can just not touch them
• When capturing images, calling arv_stream_push_buffer() too many times makes many captures fail: arv_stream_pop_buffer() says ARV_BUFFER_STATUS_CLEARED. I see that with 40 buffers, but 20 buffers works ok

Other than that, it all works perfectly. Thank you very much for making this all work.