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Diffstat (limited to 'src/libcamera/v4l2_videodevice.cpp')
-rw-r--r--src/libcamera/v4l2_videodevice.cpp69
1 files changed, 60 insertions, 9 deletions
diff --git a/src/libcamera/v4l2_videodevice.cpp b/src/libcamera/v4l2_videodevice.cpp
index 2ff25af2..9d35618d 100644
--- a/src/libcamera/v4l2_videodevice.cpp
+++ b/src/libcamera/v4l2_videodevice.cpp
@@ -25,6 +25,7 @@
#include <libcamera/file_descriptor.h>
+#include "libcamera/internal/formats.h"
#include "libcamera/internal/media_device.h"
#include "libcamera/internal/media_object.h"
@@ -579,6 +580,12 @@ int V4L2VideoDevice::open()
<< "Opened device " << caps_.bus_info() << ": "
<< caps_.driver() << ": " << caps_.card();
+ ret = getFormat(&format_);
+ if (ret) {
+ LOG(V4L2, Error) << "Failed to get format";
+ return ret;
+ }
+
return 0;
}
@@ -668,6 +675,12 @@ int V4L2VideoDevice::open(int handle, enum v4l2_buf_type type)
<< "Opened device " << caps_.bus_info() << ": "
<< caps_.driver() << ": " << caps_.card();
+ ret = getFormat(&format_);
+ if (ret) {
+ LOG(V4L2, Error) << "Failed to get format";
+ return ret;
+ }
+
return 0;
}
@@ -761,12 +774,20 @@ int V4L2VideoDevice::tryFormat(V4L2DeviceFormat *format)
*/
int V4L2VideoDevice::setFormat(V4L2DeviceFormat *format)
{
+ int ret = 0;
if (caps_.isMeta())
- return trySetFormatMeta(format, true);
+ ret = trySetFormatMeta(format, true);
else if (caps_.isMultiplanar())
- return trySetFormatMultiplane(format, true);
+ ret = trySetFormatMultiplane(format, true);
else
- return trySetFormatSingleplane(format, true);
+ ret = trySetFormatSingleplane(format, true);
+
+ /* Cache the set format on success. */
+ if (ret)
+ return ret;
+
+ format_ = *format;
+ return 0;
}
int V4L2VideoDevice::getFormatMeta(V4L2DeviceFormat *format)
@@ -1152,8 +1173,13 @@ int V4L2VideoDevice::requestBuffers(unsigned int count,
* successful return the driver's internal buffer management is initialized in
* MMAP mode, and the video device is ready to accept queueBuffer() calls.
*
- * The number of planes and the plane sizes for the allocation are determined
- * by the currently active format on the device as set by setFormat().
+ * The number of planes and their offsets and sizes are determined by the
+ * currently active format on the device as set by setFormat(). They do not map
+ * to the V4L2 buffer planes, but to colour planes of the pixel format. For
+ * instance, if the active format is formats::NV12, the allocated FrameBuffer
+ * instances will have two planes, for the luma and chroma components,
+ * regardless of whether the device uses V4L2_PIX_FMT_NV12 or
+ * V4L2_PIX_FMT_NV12M.
*
* Buffers allocated with this function shall later be free with
* releaseBuffers(). If buffers have already been allocated with
@@ -1190,8 +1216,13 @@ int V4L2VideoDevice::allocateBuffers(unsigned int count,
* usable with any V4L2 video device in DMABUF mode, or with other dmabuf
* importers.
*
- * The number of planes and the plane sizes for the allocation are determined
- * by the currently active format on the device as set by setFormat().
+ * The number of planes and their offsets and sizes are determined by the
+ * currently active format on the device as set by setFormat(). They do not map
+ * to the V4L2 buffer planes, but to colour planes of the pixel format. For
+ * instance, if the active format is formats::NV12, the allocated FrameBuffer
+ * instances will have two planes, for the luma and chroma components,
+ * regardless of whether the device uses V4L2_PIX_FMT_NV12 or
+ * V4L2_PIX_FMT_NV12M.
*
* Multiple independent sets of buffers can be allocated with multiple calls to
* this function. Device-specific limitations may apply regarding the minimum
@@ -1289,12 +1320,32 @@ std::unique_ptr<FrameBuffer> V4L2VideoDevice::createBuffer(unsigned int index)
* \todo Set the right offset once V4L2 API provides a way.
*/
plane.offset = 0;
- plane.length = multiPlanar ?
- buf.m.planes[nplane].length : buf.length;
+ plane.length = multiPlanar ? buf.m.planes[nplane].length : buf.length;
planes.push_back(std::move(plane));
}
+ const auto &info = PixelFormatInfo::info(format_.fourcc);
+ if (info.isValid() && info.numPlanes() != numPlanes) {
+ ASSERT(numPlanes == 1u);
+ const size_t numColorPlanes = info.numPlanes();
+ planes.resize(numColorPlanes);
+ const FileDescriptor &fd = planes[0].fd;
+ size_t offset = 0;
+ for (size_t i = 0; i < numColorPlanes; ++i) {
+ planes[i].fd = fd;
+ planes[i].offset = offset;
+
+ /* \todo Take the V4L2 stride into account */
+ const unsigned int vertSubSample =
+ info.planes[i].verticalSubSampling;
+ planes[i].length =
+ info.stride(format_.size.width, i, 1u) *
+ ((format_.size.height + vertSubSample - 1) / vertSubSample);
+ offset += planes[i].length;
+ }
+ }
+
return std::make_unique<FrameBuffer>(std::move(planes));
}