Intel® RealSense™ Developer Documentation

custom html

rs-save-to-disk

Saving depth and color data to PNG format

Overview

This sample demonstrates how to configure the camera for streaming in a textual environment and save depth and color data to PNG format. In addition, it touches on the subject of per-frame metadata

Expected Output

The application should run for about a second and exit after saving PNG and CSV file to disk:

Code Overview

Similar to the first tutorial we include the Cross-Platform API:

#include <librealsense2/rs.hpp> // Include RealSense Cross Platform API

We are using nothings/stb to quickly save data to disk in PNG format:

// 3rd party header for writing png files
#define STB_IMAGE_WRITE_IMPLEMENTATION
#include "stb_image_write.h"

We start like the last time by defining depth colorizer and starting the pipeline:

// Declare depth colorizer for pretty visualization of depth data
rs2::colorizer color_map;

// Declare RealSense pipeline, encapsulating the actual device and sensors
rs2::pipeline pipe;
// Start streaming with default recommended configuration
pipe.start();

We prefer not to save the absolute first frame that arrives from the device, but rather wait for auto-exposure to stabalize:

// Capture 30 frames to give autoexposure, etc. a chance to settle
for (auto i = 0; i < 30; ++i) pipe.wait_for_frames();

Intel® RealSense™ devices are not limited to just video streaming, some can offer motion tracking and 6-DOF positioning. For this example we are only interested in video frames, however:

// We can only save video frames as pngs, so we skip the rest
if (auto vf = frame.as<rs2::video_frame>())

To better visualize the depth data, we apply the colorizer on any incoming depth frames:

// Use the colorizer to get an rgb image for the depth stream
if (vf.is<rs2::depth_frame>()) vf = color_map(frame);

Then we save frame data to PNG:

stbi_write_png(png_file.str().c_str(), vf.get_width(), vf.get_height(),
               vf.get_bytes_per_pixel(), vf.get_data(), vf.get_stride_in_bytes());

Each frame may come with some metadata feilds. We iterate over all possible metadata feilds and save to CSV these that are available:

// Record all the available metadata attributes
for (size_t i = 0; i < RS2_FRAME_METADATA_COUNT; i++)
{
    if (frm.supports_frame_metadata((rs2_frame_metadata)i))
    {
        csv << rs2_frame_metadata_to_string((rs2_frame_metadata)i) << ","
            << frm.get_frame_metadata((rs2_frame_metadata)i) << "\n";
    }
}

Please see per-frame metadata for more information.

rs-save-to-disk


Saving depth and color data to PNG format

Suggested Edits are limited on API Reference Pages

You can only suggest edits to Markdown body content, but not to the API spec.