Allow wrap external data into VideoFrame

Author: h4tr3d

src/frame.cpp

@@ -81,11 +81,20 @@ int av_frame_copy(AVFrame *dst, const AVFrame *src)
 
 #endif // LIBAVUTIL_VERSION_INT <= 53.5.0 (ffmpeg 2.2)
 
+void avcpp_null_deleter(void* /*opaque*/, uint8_t */*data*/)
+{
+}
+
 } // anonymous namespace
 
 namespace av
 {
 
+VideoFrame::VideoFrame()
+{
+
+}
+
 VideoFrame::VideoFrame(PixelFormat pixelFormat, int width, int height, int align)
 {
     m_raw->format = pixelFormat;
@@ -231,6 +240,49 @@ bool VideoFrame::copyToBuffer(std::vector<uint8_t> &dst, int align, OptionalErro
     return copyToBuffer(dst.data(), dst.size(), align, ec);
 }
 
+namespace {
+VideoFrame _wrap(const void *data, size_t size, PixelFormat pixelFormat, int width, int height, int align,
+                 void (*deleter)(void *opaque, uint8_t *data), void *opaque)
+{
+    VideoFrame out;
+
+    auto frame = out.raw();
+
+    frame->format = pixelFormat;
+    frame->width  = width;
+    frame->height = height;
+
+    // setup buffers
+    frame->buf[0] = av_buffer_create(const_cast<uint8_t*>(static_cast<const uint8_t*>(data)), size, deleter, opaque, AV_BUFFER_FLAG_READONLY);
+
+    av_image_fill_arrays(frame->data,
+                         frame->linesize,
+                         frame->buf[0]->data,
+                         pixelFormat, width, height, align);
+
+    frame->extended_data = frame->data;
+
+    return out;
+}
+}
+
+VideoFrame VideoFrame::wrap(const void *data, size_t size, PixelFormat pixelFormat, int width, int height, int align)
+{
+    return _wrap(data, size, pixelFormat, width, height, align, avcpp_null_deleter, nullptr);
+}
+
+#ifdef __cpp_lib_span
+VideoFrame VideoFrame::wrap(std::span<const std::byte> data, PixelFormat pixelFormat, int width, int height, int align)
+{
+    return wrap(data.data(), data.size(), pixelFormat, width, height, align);
+}
+
+VideoFrame VideoFrame::wrap(std::span<const std::byte> data, void (*deleter)(void *opaque, uint8_t *data),
+    void *opaque, PixelFormat pixelFormat, int width, int height, int align)
+{
+    return _wrap(data.data(), data.size(), pixelFormat, width, height, align, deleter, opaque);
+}
+#endif
 
 AudioSamples::AudioSamples(SampleFormat sampleFormat, int samplesCount, uint64_t channelLayout, int sampleRate, int align)
 {

src/frame.h

@@ -385,6 +385,56 @@ class VideoFrame : public Frame<VideoFrame>
     size_t                 bufferSize(int align = 1, OptionalErrorCode ec = throws()) const;
     bool                   copyToBuffer(uint8_t *dst, size_t size, int align = 1, OptionalErrorCode ec = throws());
     bool                   copyToBuffer(std::vector<uint8_t>& dst, int align = 1, OptionalErrorCode ec = throws());
+
+
+    /**
+     * Wrap external data into VideoFrame object ready to use with FFmpeg/AvCpp.
+     *
+     * @note Ownershipping does not acquired.
+     *
+     * @param data          data pointer to wrap
+     * @param size          whole data buffer size with alignment and real data
+     * @param pixelFormat   pixel format of the data
+     * @param width         image width
+     * @param height        image height
+     * @param align         image data alignemnt
+     *
+     * @return image data wrapped into VideoFrame object
+     */
+    static VideoFrame wrap(const void *data, size_t size, PixelFormat pixelFormat, int width, int height, int align = 1);
+
+#ifdef __cpp_lib_span
+    /**
+     * Wrap external data into VideoFrame object ready to use with FFmpeg/AvCpp.
+     *
+     * @note Ownershipping does not acquired.
+
+     * @param data           external image data wrapped into std::span
+     * @param pixelFormat    pixel format of the data
+     * @param width          image width
+     * @param height         image height
+     * @param align          image data alignment
+     * @return
+     */
+    static VideoFrame wrap(std::span<const std::byte> data, PixelFormat pixelFormat, int width, int height, int align = 1);
+
+    /**
+     * Wrap external data into VideoFrame object ready to use with FFmpeg/AvCpp.
+     *
+     * @note Ownershipping does not acquired. When data wants to be deleted, passed deleter function will be called.
+
+     * @param data           external image data wrapped into std::span
+     * @param deleter        user defined deleter
+     * @param opaque         opaque data passed to the deleter, maybe nullptr
+     * @param pixelFormat    pixel format of the data
+     * @param width          image width
+     * @param height         image height
+     * @param align          image data alignment
+     * @return
+     */
+    static VideoFrame wrap(std::span<const std::byte> data, void (*deleter)(void *opaque, uint8_t *data),
+                           void *opaque, PixelFormat pixelFormat, int width, int height, int align = 1);
+#endif
 };