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// The contents of this file are in the public domain. See LICENSE_FOR_EXAMPLE_PROGRAMS.txt
/*
This is an example illustrating the use of the ffmpeg wrappers,
in this case the decoding API.
This is a pretty simple example. It loads a raw codec file, parses chunks of
data to the decoder, plots images to a GUI window, and counts audio samples.
*/
#include <cstdio>
#include <dlib/media.h>
#include <dlib/gui_widgets.h>
#include <dlib/cmd_line_parser.h>
using namespace std;
using namespace dlib;
using namespace dlib::ffmpeg;
int main(const int argc, const char** argv)
try
{
command_line_parser parser;
parser.add_option("i", "input video encoded stream. e.g. dlib/test/ffmpeg_data/MOT20-08-raw.h264", 1);
parser.add_option("codec", "codec name. e.g. h264", 1);
parser.set_group_name("Help Options");
parser.add_option("h", "alias of --help");
parser.add_option("help", "display this message and exit");
parser.parse(argc, argv);
const char* one_time_opts[] = {"i"};
parser.check_one_time_options(one_time_opts);
if (parser.option("h") || parser.option("help"))
{
parser.print_options();
return 0;
}
const std::string filepath = parser.option("i").argument();
const std::string codec = parser.option("codec").argument();
decoder dec([&] {
decoder::args args;
args.codec_name = codec;
return args;
}());
if (!dec.is_open())
{
printf("Failed to create decoder.\n");
return EXIT_FAILURE;
}
frame f;
array2d<rgb_pixel> img;
int samples{0};
image_window win;
// When reading frames, we get exactly what's in the codec by default.
// To resize, change pixel format, resample or change sample format,
// you have to pass extra arguments to wrap() which either resizes or resamples
// the frame. Since we want rgb_pixel, we need to set the pixel format appropriately.
const resizing_args args_image {0, 0, pix_traits<rgb_pixel>::fmt};
const auto callback = [&](frame& f)
{
if (f.is_image())
{
convert(f, img);
win.set_image(img);
}
else if (f.is_audio())
{
samples += f.nsamples();
}
};
ifstream fin{filepath, std::ios::binary};
std::vector<char> buf(1024);
while (fin)
{
fin.read(buf.data(), buf.size());
size_t ret = fin.gcount();
dec.push((const uint8_t*)buf.data(), ret, wrap(callback, args_image));
}
dec.flush(wrap(callback, args_image));
printf("Read %i audio samples\n", samples);
return EXIT_SUCCESS;
}
catch (const std::exception& e)
{
printf("%s\n", e.what());
return EXIT_FAILURE;
}
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