Copy codec parameters from context

Now that the recorder have access to the codec context, it may
automatically initialize the stream codec parameters.

The V4L2 sink could do the same.

app/src/recorder.c

@@ -473,9 +473,12 @@ sc_recorder_video_packet_sink_open(struct sc_packet_sink *sink,
         return false;
     }
 
-    stream->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
-    stream->codecpar->codec_id = ctx->codec->id;
-    stream->codecpar->format = AV_PIX_FMT_YUV420P;
+    int r = avcodec_parameters_from_context(stream->codecpar, ctx);
+    if (r < 0) {
+        sc_mutex_unlock(&recorder->mutex);
+        return false;
+    }
+
     stream->codecpar->width = recorder->declared_frame_size.width;
     stream->codecpar->height = recorder->declared_frame_size.height;
 
@@ -554,15 +557,11 @@ sc_recorder_audio_packet_sink_open(struct sc_packet_sink *sink,
         return false;
     }
 
-    stream->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
-    stream->codecpar->codec_id = ctx->codec->id;
-#ifdef SCRCPY_LAVU_HAS_CHLAYOUT
-    stream->codecpar->ch_layout.nb_channels = 2;
-#else
-    stream->codecpar->channel_layout = AV_CH_LAYOUT_STEREO;
-    stream->codecpar->channels = 2;
-#endif
-    stream->codecpar->sample_rate = 48000;
+    int r = avcodec_parameters_from_context(stream->codecpar, ctx);
+    if (r < 0) {
+        sc_mutex_unlock(&recorder->mutex);
+        return false;
+    }
 
     recorder->audio_stream_index = stream->index;
 

app/src/v4l2_sink.c

@@ -205,9 +205,11 @@ sc_v4l2_sink_open(struct sc_v4l2_sink *vs, const AVCodecContext *ctx) {
         goto error_avformat_free_context;
     }
 
-    ostream->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
-    ostream->codecpar->codec_id = encoder->id;
-    ostream->codecpar->format = AV_PIX_FMT_YUV420P;
+    int r = avcodec_parameters_from_context(ostream->codecpar, ctx);
+    if (r < 0) {
+        goto error_avformat_free_context;
+    }
+
     ostream->codecpar->width = vs->frame_size.width;
     ostream->codecpar->height = vs->frame_size.height;