From a7f24a8d9ab5512abb04b12c1feb6972633961e5 Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Tue, 17 Mar 2020 01:17:29 +0200 Subject: libcamera: v4l2_videodevice: Add V4L2PixelFormat class MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The V4L2PixelFormat class describes the pixel format of a V4L2 buffer. It wraps the V4L2 numerical FourCC, and shall be used in all APIs that deal with V4L2 pixel formats. Its purpose is to prevent unintentional confusion of V4L2 and DRM FourCCs in code by catching implicit conversion attempts at compile time. The constructor taking a V4L2 FourCC integer value will be made explicit in a further commit to minimize the size of this change and keep it reviewable. Signed-off-by: Laurent Pinchart Reviewed-by: Niklas Söderlund Reviewed-by: Jacopo Mondi --- src/libcamera/v4l2_videodevice.cpp | 91 +++++++++++++++++++++++++++++++------- 1 file changed, 76 insertions(+), 15 deletions(-) (limited to 'src/libcamera/v4l2_videodevice.cpp') diff --git a/src/libcamera/v4l2_videodevice.cpp b/src/libcamera/v4l2_videodevice.cpp index 56251a46..1c60014c 100644 --- a/src/libcamera/v4l2_videodevice.cpp +++ b/src/libcamera/v4l2_videodevice.cpp @@ -278,6 +278,65 @@ bool V4L2BufferCache::Entry::operator==(const FrameBuffer &buffer) const return true; } +/** + * \class V4L2PixelFormat + * \brief V4L2 pixel format FourCC wrapper + * + * The V4L2PixelFormat class describes the pixel format of a V4L2 buffer. It + * wraps the V4L2 numerical FourCC, and shall be used in all APIs that deal with + * V4L2 pixel formats. Its purpose is to prevent unintentional confusion of + * V4L2 and DRM FourCCs in code by catching implicit conversion attempts at + * compile time. + */ + +/** + * \fn V4L2PixelFormat::V4L2PixelFormat() + * \brief Construct a V4L2PixelFormat with an invalid format + * + * V4L2PixelFormat instances constructed with the default constructor are + * invalid, calling the isValid() function returns false. + */ + +/** + * \fn V4L2PixelFormat::V4L2PixelFormat(uint32_t fourcc) + * \brief Construct a V4L2PixelFormat from a FourCC value + * \param[in] fourcc The pixel format FourCC numerical value + */ + +/** + * \fn bool V4L2PixelFormat::isValid() const + * \brief Check if the pixel format is valid + * + * V4L2PixelFormat instances constructed with the default constructor are + * invalid. Instances constructed with a FourCC defined in the V4L2 API are + * valid. The behaviour is undefined otherwise. + * + * \return True if the pixel format is valid, false otherwise + */ + +/** + * \fn uint32_t V4L2PixelFormat::fourcc() const + * \brief Retrieve the pixel format FourCC numerical value + * \return The pixel format FourCC numerical value + */ + +/** + * \fn V4L2PixelFormat::operator uint32_t() const + * \brief Convert to the pixel format FourCC numerical value + * \return The pixel format FourCC numerical value + */ + +/** + * \brief Assemble and return a string describing the pixel format + * \return A string describing the pixel format + */ +std::string V4L2PixelFormat::toString() const +{ + char str[11]; + snprintf(str, 11, "0x%08x", fourcc_); + return str; +} + /** * \class V4L2DeviceFormat * \brief The V4L2 video device image format and sizes @@ -386,7 +445,7 @@ bool V4L2BufferCache::Entry::operator==(const FrameBuffer &buffer) const const std::string V4L2DeviceFormat::toString() const { std::stringstream ss; - ss << size.toString() << "-" << utils::hex(fourcc); + ss << size.toString() << "-" << fourcc.toString(); return ss.str(); } @@ -901,29 +960,31 @@ int V4L2VideoDevice::setFormatSingleplane(V4L2DeviceFormat *format) * * \return A list of the supported video device formats */ -ImageFormats V4L2VideoDevice::formats() +std::map> V4L2VideoDevice::formats() { - ImageFormats formats; + std::map> formats; - for (unsigned int pixelformat : enumPixelformats()) { - std::vector sizes = enumSizes(pixelformat); + for (V4L2PixelFormat pixelFormat : enumPixelformats()) { + std::vector sizes = enumSizes(pixelFormat); if (sizes.empty()) return {}; - if (formats.addFormat(pixelformat, sizes)) { + if (formats.find(pixelFormat) != formats.end()) { LOG(V4L2, Error) << "Could not add sizes for pixel format " - << pixelformat; + << pixelFormat; return {}; } + + formats.emplace(pixelFormat, sizes); } return formats; } -std::vector V4L2VideoDevice::enumPixelformats() +std::vector V4L2VideoDevice::enumPixelformats() { - std::vector formats; + std::vector formats; int ret; for (unsigned int index = 0; ; index++) { @@ -948,7 +1009,7 @@ std::vector V4L2VideoDevice::enumPixelformats() return formats; } -std::vector V4L2VideoDevice::enumSizes(unsigned int pixelFormat) +std::vector V4L2VideoDevice::enumSizes(V4L2PixelFormat pixelFormat) { std::vector sizes; int ret; @@ -1563,7 +1624,7 @@ V4L2VideoDevice *V4L2VideoDevice::fromEntityName(const MediaDevice *media, * \param[in] v4l2Fourcc The V4L2 pixel format (V4L2_PIX_FORMAT_*) * \return The PixelFormat corresponding to \a v4l2Fourcc */ -PixelFormat V4L2VideoDevice::toPixelFormat(uint32_t v4l2Fourcc) +PixelFormat V4L2VideoDevice::toPixelFormat(V4L2PixelFormat v4l2Fourcc) { switch (v4l2Fourcc) { /* RGB formats. */ @@ -1612,7 +1673,7 @@ PixelFormat V4L2VideoDevice::toPixelFormat(uint32_t v4l2Fourcc) libcamera::_log(__FILE__, __LINE__, _LOG_CATEGORY(V4L2)(), LogError).stream() << "Unsupported V4L2 pixel format " - << utils::hex(v4l2Fourcc); + << v4l2Fourcc.toString(); return PixelFormat(); } } @@ -1628,7 +1689,7 @@ PixelFormat V4L2VideoDevice::toPixelFormat(uint32_t v4l2Fourcc) * * \return The V4L2_PIX_FMT_* pixel format code corresponding to \a pixelFormat */ -uint32_t V4L2VideoDevice::toV4L2Fourcc(const PixelFormat &pixelFormat) +V4L2PixelFormat V4L2VideoDevice::toV4L2Fourcc(const PixelFormat &pixelFormat) { return V4L2VideoDevice::toV4L2Fourcc(pixelFormat, caps_.isMultiplanar()); } @@ -1646,8 +1707,8 @@ uint32_t V4L2VideoDevice::toV4L2Fourcc(const PixelFormat &pixelFormat) * * \return The V4L2_PIX_FMT_* pixel format code corresponding to \a pixelFormat */ -uint32_t V4L2VideoDevice::toV4L2Fourcc(const PixelFormat &pixelFormat, - bool multiplanar) +V4L2PixelFormat V4L2VideoDevice::toV4L2Fourcc(const PixelFormat &pixelFormat, + bool multiplanar) { switch (pixelFormat) { /* RGB formats. */ -- cgit v1.2.1