feat: add flag to disable adaptive stream

Author: TzuHuanTai

src/args.h

@@ -18,6 +18,7 @@ struct Args {
     bool no_audio = false;
     bool hw_accel = false;
     bool use_libcamera = false;
+    bool fixed_resolution = false;
     uint32_t format = V4L2_PIX_FMT_MJPEG;
     std::string v4l2_format = "mjpeg";
     std::string device = "/dev/video0";

src/customized_video_encoder_factory.cpp

@@ -49,7 +49,7 @@ std::unique_ptr<webrtc::VideoEncoder>
 CustomizedVideoEncoderFactory::CreateVideoEncoder(const webrtc::SdpVideoFormat &format) {
     if (absl::EqualsIgnoreCase(format.name, cricket::kH264CodecName)) {
         if (args_.hw_accel) {
-            return V4l2H264Encoder::Create();
+            return V4l2H264Encoder::Create(args_);
         } else {
             return webrtc::H264Encoder::Create(cricket::VideoCodec(format));
         }

src/parser.cpp

@@ -40,6 +40,8 @@ void Parser::ParseArgs(int argc, char *argv[], Args &args) {
         ("use_libcamera", bpo::bool_switch()->default_value(args.use_libcamera),
             "Read YUV420 from the camera via libcamera, the `device` and `v4l2_format` "
             "flags will be suspended")
+        ("fixed_resolution", bpo::bool_switch()->default_value(args.fixed_resolution),
+            "Disable adaptive resolution scaling and keep a fixed resolution.")
         ("no_audio", bpo::bool_switch()->default_value(args.no_audio), "Run without audio source")
         ("uid", bpo::value<std::string>()->default_value(args.uid),
             "Set the unique id to identify the device")
@@ -108,6 +110,7 @@ void Parser::ParseArgs(int argc, char *argv[], Args &args) {
     SetIfExists(vm, "record_path", args.record_path);
 
     args.use_libcamera = vm["use_libcamera"].as<bool>();
+    args.fixed_resolution = vm["fixed_resolution"].as<bool>();
     args.no_audio = vm["no_audio"].as<bool>();
     args.hw_accel = vm["hw_accel"].as<bool>();
 

src/track/scale_track_source.cpp

@@ -38,8 +38,11 @@ void ScaleTrackSource::OnFrameCaptured(rtc::scoped_refptr<webrtc::VideoFrameBuff
         timestamp_aligner.TranslateTimestamp(timestamp_us, rtc::TimeMicros());
 
     int adapted_width, adapted_height, crop_width, crop_height, crop_x, crop_y;
-    if (!AdaptFrame(width, height, timestamp_us, &adapted_width, &adapted_height, &crop_width,
-                    &crop_height, &crop_x, &crop_y)) {
+    if (capturer->config().fixed_resolution) {
+        adapted_width = width;
+        adapted_height = height;
+    } else if (!AdaptFrame(width, height, timestamp_us, &adapted_width, &adapted_height,
+                           &crop_width, &crop_height, &crop_x, &crop_y)) {
         return;
     }
 

src/track/v4l2dma_track_source.cpp

@@ -36,20 +36,28 @@ void V4l2DmaTrackSource::OnFrameCaptured(V4l2Buffer decoded_buffer) {
     const int64_t translated_timestamp_us =
         timestamp_aligner.TranslateTimestamp(timestamp_us, rtc::TimeMicros());
 
-    int adapted_width, adapted_height, crop_width, crop_height, crop_x, crop_y;
-    if (!AdaptFrame(width, height, timestamp_us, &adapted_width, &adapted_height, &crop_width,
-                    &crop_height, &crop_x, &crop_y)) {
-        return;
-    }
+    if (capturer->config().fixed_resolution) {
+        auto dst_buffer = V4l2FrameBuffer::Create(config_width_, config_height_, decoded_buffer,
+                                                  V4L2_PIX_FMT_YUV420);
+        OnFrame(webrtc::VideoFrame::Builder()
+                    .set_video_frame_buffer(dst_buffer)
+                    .set_rotation(webrtc::kVideoRotation_0)
+                    .set_timestamp_us(translated_timestamp_us)
+                    .build());
+    } else {
+        int adapted_width, adapted_height, crop_width, crop_height, crop_x, crop_y;
+        if (!AdaptFrame(width, height, timestamp_us, &adapted_width, &adapted_height, &crop_width,
+                        &crop_height, &crop_x, &crop_y)) {
+            return;
+        }
 
-    if (adapted_width != config_width_ || adapted_height != config_height_) {
-        config_width_ = adapted_width;
-        config_height_ = adapted_height;
-        scaler =
-            V4l2Scaler::Create(width, height, config_width_, config_height_, is_dma_src_, true);
-    }
+        if (!scaler || adapted_width != config_width_ || adapted_height != config_height_) {
+            config_width_ = adapted_width;
+            config_height_ = adapted_height;
+            scaler =
+                V4l2Scaler::Create(width, height, config_width_, config_height_, is_dma_src_, true);
+        }
 
-    if (scaler) {
         scaler->EmplaceBuffer(
             decoded_buffer, [this, translated_timestamp_us](V4l2Buffer scaled_buffer) {
                 auto dst_buffer = V4l2FrameBuffer::Create(config_width_, config_height_,
@@ -61,13 +69,5 @@ void V4l2DmaTrackSource::OnFrameCaptured(V4l2Buffer decoded_buffer) {
                             .set_timestamp_us(translated_timestamp_us)
                             .build());
             });
-    } else {
-        auto dst_buffer = V4l2FrameBuffer::Create(config_width_, config_height_, decoded_buffer,
-                                                  V4L2_PIX_FMT_YUV420);
-        OnFrame(webrtc::VideoFrame::Builder()
-                    .set_video_frame_buffer(dst_buffer)
-                    .set_rotation(webrtc::kVideoRotation_0)
-                    .set_timestamp_us(translated_timestamp_us)
-                    .build());
     }
 }

src/v4l2_codecs/v4l2_h264_encoder.cpp

@@ -2,13 +2,13 @@
 #include "common/logging.h"
 #include "common/v4l2_frame_buffer.h"
 
-std::unique_ptr<webrtc::VideoEncoder> V4l2H264Encoder::Create() {
-    return std::make_unique<V4l2H264Encoder>();
+std::unique_ptr<webrtc::VideoEncoder> V4l2H264Encoder::Create(Args args) {
+    return std::make_unique<V4l2H264Encoder>(args);
 }
 
-V4l2H264Encoder::V4l2H264Encoder()
-    : fps_adjuster_(30),
-      is_dma_(true),
+V4l2H264Encoder::V4l2H264Encoder(Args args)
+    : fps_adjuster_(args.fps),
+      is_dma_(!args.fixed_resolution),
       bitrate_adjuster_(.85, 1),
       callback_(nullptr) {}
 

src/v4l2_codecs/v4l2_h264_encoder.h

@@ -6,12 +6,13 @@
 #include <common_video/include/bitrate_adjuster.h>
 #include <modules/video_coding/codecs/h264/include/h264.h>
 
+#include "args.h"
 #include "v4l2_codecs/v4l2_encoder.h"
 
 class V4l2H264Encoder : public webrtc::VideoEncoder {
   public:
-    static std::unique_ptr<webrtc::VideoEncoder> Create();
-    V4l2H264Encoder();
+    static std::unique_ptr<webrtc::VideoEncoder> Create(Args args);
+    V4l2H264Encoder(Args args);
 
     int32_t InitEncode(const webrtc::VideoCodec *codec_settings,
                        const VideoEncoder::Settings &settings) override;