Allow feed labels in config

AppConfig.cpp

@@ -660,6 +660,12 @@ bool applyConfigFile(
             feed.kind = FeedKind::MxlSdk;
         }
 
+        if (const std::string* label =
+                jsonString(objectField(*feedObject, "label")))
+        {
+            feed.label = *label;
+        }
+
         config.feeds[i] = std::move(feed);
     }
 

AppConfig.hpp

@@ -35,6 +35,7 @@ struct FeedConfig
     FeedKind kind = FeedKind::NoSignal;
     std::string mxlDomain;
     std::string mxlFlowId;
+    std::string label;
 };
 
 struct AppConfig

MxlSdkFeed.cpp

@@ -160,10 +160,10 @@ namespace
     {
         const char* keys[] =
         {
-            "name",
+            "label",
-            "flow_name",
             "description",
-            "label"
+            "flow_name",
+            "name"
         };
 
         for (const char* key : keys)

PixelFormat.hpp

@@ -95,6 +95,8 @@ inline void decodeV210Line(
             default: y10 = y0; cb10 = cb0; cr10 = cr0; break;
         }
 
+        // BT.709 limited-range YCbCr to RGB. v210 stores 10-bit video-range
+        // samples: Y [64, 940], Cb/Cr centered at 512.
         int32_t yp  = (static_cast<int32_t>(y10) - 64) >> 2;
         int32_t cbp = (static_cast<int32_t>(cb10) - 512) >> 2;
         int32_t crp = (static_cast<int32_t>(cr10) - 512) >> 2;
@@ -175,6 +177,8 @@ inline void convertV210ToRgba(
                 default: y10 = y0; cb10 = cb0; cr10 = cr0; break;
             }
 
+            // BT.709 limited-range YCbCr to RGB. v210 stores 10-bit video-range
+            // samples: Y [64, 940], Cb/Cr centered at 512.
             int32_t yp  = (static_cast<int32_t>(y10) - 64) >> 2;
             int32_t cbp = (static_cast<int32_t>(cb10) - 512) >> 2;
             int32_t crp = (static_cast<int32_t>(cr10) - 512) >> 2;
@@ -187,4 +191,4 @@ inline void convertV210ToRgba(
                 {clampUint8(r), clampUint8(g), clampUint8(b)});
         }
     }
-}
+}

README.md

@@ -0,0 +1,99 @@
+# MXL Multiviewer
+
+Small Vulkan/SDL3 multiviewer for test feeds and MXL SDK video flows.
+
+## Dependencies
+
+Install:
+
+- CMake 3.20+
+- C++20 compiler
+- Vulkan loader and headers
+- Vulkan driver for the target GPU
+- SDL3 development package with `pkg-config` support
+- `glslangValidator`
+
+On Ubuntu/Debian-like systems the packages are usually similar to:
+
+```bash
+sudo apt install cmake g++ pkg-config libvulkan-dev vulkan-tools glslang-tools libsdl3-dev
+```
+
+Check that the discrete GPU is visible:
+
+```bash
+vulkaninfo --summary
+```
+
+## Build Without MXL SDK
+
+This builds synthetic feeds, SMPTE bars, and no-signal mode:
+
+```bash
+cmake -S . -B build -DCMAKE_BUILD_TYPE=Release
+cmake --build build -j
+```
+
+Run a synthetic v210 test grid:
+
+```bash
+./build/mxl_multiviewer --perf --grid 4x4 v210 v210 v210 v210 v210 v210 v210 v210 v210
+```
+
+## Build With MXL SDK
+
+Set `MXL_SDK_ROOT` to the SDK checkout/root that contains `lib/include` and `build/Linux-Clang-Release/lib`:
+
+```bash
+cmake -S . -B build-sdk \
+  -DCMAKE_BUILD_TYPE=Release \
+  -DMXL_MULTIVIEWER_ENABLE_MXL_SDK=ON \
+  -DMXL_SDK_ROOT=/path/to/mxl-sdk
+
+cmake --build build-sdk -j
+```
+
+Run with an existing feed config:
+
+```bash
+./build-sdk/mxl_multiviewer --perf --grid 4x4 --config /tmp/feeds_config.json
+```
+
+Each feed object can include an optional `label` field to override the tile UI text:
+
+```json
+{
+  "domain": "/tmp/mxl",
+  "flow": "853a9cda-0f7a-4b48-b2df-b3f628440150",
+  "label": "Camera 1"
+}
+```
+
+Useful probe flags:
+
+```bash
+--v210-upload-worker
+--adaptive-feed-texture
+--v210-staging-memory default|cached|device-local
+```
+
+Example:
+
+```bash
+./build-sdk/mxl_multiviewer \
+  --adaptive-feed-texture \
+  --v210-upload-worker \
+  --perf \
+  --grid 4x4 \
+  --config /tmp/feeds_config.json
+```
+
+## Notes
+
+- Run from the repository root or keep the `shaders/` directory next to the executable path expected by the app.
+- If SDL opens on the wrong GPU/session, try running from the desktop session attached to the discrete GPU and confirm with `vulkaninfo --summary`.
+- `v210_test` is a CPU-side conversion sanity check:
+
+```bash
+./build/v210_test
+```

V210ComputeDecoder.cpp

@@ -330,7 +330,7 @@ void V210ComputeDecoder::createFeedResources(
     imageInfo.imageLayout = VK_IMAGE_LAYOUT_GENERAL;
     imageInfo.imageView = feed.imageView;
 
-    VkWriteDescriptorSet writes[2];
+    VkWriteDescriptorSet writes[2]{};
 
     writes[0].sType = VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET;
     writes[0].dstSet = feed.descriptorSet;

config.example.json

@@ -7,11 +7,13 @@
   "feeds": [
     {
       "domain": "/tmp/mxl",
-      "flow": "853a9cda-0f7a-4b48-b2df-b3f628440150"
+      "flow": "853a9cda-0f7a-4b48-b2df-b3f628440150",
+      "label": "Camera 1"
     },
     {
       "domain": "/tmp/mxl",
-      "flow": "fab60e17-f721-4e12-a7dd-312f5f6e502d"
+      "flow": "fab60e17-f721-4e12-a7dd-312f5f6e502d",
+      "label": "Camera 2"
     },
     {
       "kind": "nosignal"

main.cpp

@@ -464,6 +464,7 @@ static ImU32 tileLabelColor(
 
 static void drawTileLabels(
     const std::vector<std::unique_ptr<IVideoFeed>>& feeds,
+    const std::vector<FeedConfig>& feedConfigs,
     uint32_t gridCols,
     uint32_t gridRows)
 {
@@ -492,12 +493,20 @@ static void drawTileLabels(
             feeds[i]->status();
         const std::string sourceInfo =
             feeds[i]->sourceInfo();
+        const std::string labelOverride =
+            i < feedConfigs.size()
+                ? feedConfigs[i].label
+                : "";
+        const std::string labelText =
+            !labelOverride.empty()
+                ? labelOverride
+                : sourceInfo.empty()
+                ? feedRuntimeStatusDisplayName(status)
+                : sourceInfo;
         const std::string label =
             std::to_string(i + 1) +
             ": " +
-            (sourceInfo.empty()
+            labelText;
-                ? feedRuntimeStatusDisplayName(status)
-                : sourceInfo);
 
         const ImVec2 labelMin(
             tileRect.x0,
@@ -514,10 +523,21 @@ static void drawTileLabels(
             labelMax,
             IM_COL32(0, 0, 0, 175)
         );
+        const ImVec4 labelClip(
+            labelMin.x,
+            labelMin.y,
+            labelMax.x,
+            labelMax.y
+        );
         drawList->AddText(
+            nullptr,
+            0.0f,
             textPos,
             tileLabelColor(status),
-            label.c_str()
+            label.c_str(),
+            nullptr,
+            0.0f,
+            &labelClip
         );
     }
 }
@@ -705,6 +725,12 @@ int main(int argc, char* argv[])
                 << " flowId=" << config.feeds[i].mxlFlowId;
         }
 
+        if (!config.feeds[i].label.empty())
+        {
+            std::cout
+                << " label=\"" << config.feeds[i].label << "\"";
+        }
+
         std::cout << std::endl;
 
         feeds[i] = createFeed(
@@ -1798,6 +1824,7 @@ int main(int argc, char* argv[])
 
         drawTileLabels(
             feeds,
+            config.feeds,
             config.gridCols,
             config.gridRows
         );

shaders/v210_decode.comp

@@ -62,6 +62,8 @@ void main()
         default: y10 = y5;  cb10 = cb4; cr10 = cr4; break;
     }
 
+    // BT.709 limited-range YCbCr to RGB. v210 stores 10-bit video-range
+    // samples: Y [64, 940], Cb/Cr centered at 512.
     int yp  = int(y10) - 64;
     int cbp = int(cb10) - 512;
     int crp = int(cr10) - 512;
@@ -79,4 +81,4 @@ void main()
     b = clamp(b, 0, 255);
 
     imageStore(dstImage, dstPos, vec4(float(r) / 255.0, float(g) / 255.0, float(b) / 255.0, 1.0));
-}
+}