feat(app): add mk-moshable

CMakeLists.txt

@@ -18,8 +18,15 @@ target_link_libraries(mosh-me avcpp::avcpp spdlog::spdlog)
 target_compile_features(mosh-me PUBLIC cxx_std_23)
 target_include_directories(mosh-me PRIVATE ${PROJECT_SOURCE_DIR}/include)
 
+add_executable(mk-moshable
+    ${PROJECT_SOURCE_DIR}/app/mk-moshable.cpp
+)
+target_link_libraries(mk-moshable avcpp::avcpp spdlog::spdlog)
+target_compile_features(mk-moshable PUBLIC cxx_std_23)
+target_include_directories(mk-moshable PRIVATE ${PROJECT_SOURCE_DIR}/include)
 
-install(TARGETS mosh-me mosh-me)
+
+install(TARGETS mosh-me mk-moshable)
 
 ################################################################################
 

app/mk-moshable.cpp

@@ -0,0 +1,89 @@
+#include <avcpp/av.h>
+#include <avcpp/codeccontext.h>
+#include <avcpp/formatcontext.h>
+#include <avcpp/stream.h>
+#include <spdlog/spdlog.h>
+
+int main(int argc, char *argv[]) {
+  if (argc < 3) {
+    spdlog::error("Please invoke with {} <ifile> <ofile>", argv[0]);
+  }
+
+  av::init();
+
+  try {
+
+    av::FormatContext ictx;
+    ictx.openInput(argv[1]);
+    ictx.findStreamInfo();
+
+    off_t v_istream_ix = -1;
+    for (off_t i = 0; i < ictx.streamsCount(); i++) {
+      auto stream = ictx.stream(i);
+      if (stream.isVideo() && stream.isValid()) {
+        v_istream_ix = i;
+      }
+    }
+    if (v_istream_ix == -1) {
+      spdlog::error("No video stream found in {}", argv[1]);
+      return 1;
+    }
+    av::VideoDecoderContext decoder(ictx.stream(v_istream_ix));
+    decoder.open();
+
+    av::FormatContext octx;
+    av::OutputFormat ofmt;
+    ofmt.setFormat("", argv[2]);
+    octx.setFormat(ofmt);
+    auto ocodec = av::findEncodingCodec("libxvid");
+    av::VideoEncoderContext encoder(ocodec);
+    encoder.setPixelFormat(decoder.pixelFormat());
+    encoder.setWidth(decoder.width());
+    encoder.setHeight(decoder.height());
+    encoder.setGopSize(1000);
+    encoder.setMaxBFrames(0);
+    encoder.setGlobalQuality(1);
+    encoder.raw()->qmin = 1;
+    encoder.raw()->qmax = 1;
+    encoder.setFlags(AV_CODEC_FLAG_QPEL | AV_CODEC_FLAG_4MV);
+    encoder.setTimeBase({1, 1000});
+
+    encoder.open();
+
+    auto ostream = octx.addStream(encoder);
+    ostream.setFrameRate(ictx.stream(v_istream_ix).frameRate());
+
+    octx.openOutput(argv[2]);
+    octx.writeHeader();
+
+    for (;;) {
+      auto pkt = ictx.readPacket();
+      if (pkt.isNull()) {
+        break;
+      }
+
+      if (pkt.streamIndex() != v_istream_ix) {
+        continue;
+      }
+
+      auto frame = decoder.decode(pkt);
+
+      if (frame) {
+        frame.setTimeBase(encoder.timeBase());
+        frame.setStreamIndex(0);
+        frame.setPictureType();
+
+        auto opkt = encoder.encode(frame);
+        if (opkt) {
+          opkt.setStreamIndex(0);
+          octx.writePacket(opkt);
+        }
+      }
+    }
+
+    octx.writeTrailer();
+    octx.flush();
+  } catch (const av::Exception &e) {
+    spdlog::error("{}", e.what());
+  }
+}