From 4c42086f0941a75554cc96077f1c08cee6168f48 Mon Sep 17 00:00:00 2001
From: Cameron Gutman <aicommander@gmail.com>
Date: Sun, 27 Oct 2024 20:32:05 -0500
Subject: [PATCH] feat(vaapi): add option to enable strict enforcement of frame
 size

---
 docs/configuration.md                         | 27 ++++++++++++++++++
 src/config.cpp                                |  6 ++++
 src/config.h                                  |  4 +++
 src/platform/linux/vaapi.cpp                  | 12 ++++----
 src_assets/common/assets/web/config.html      | 11 ++++++--
 .../web/configs/tabs/ContainerEncoders.vue    |  8 ++++++
 .../configs/tabs/encoders/VAAPIEncoder.vue    | 28 +++++++++++++++++++
 .../assets/web/public/assets/locale/en.json   |  2 ++
 8 files changed, 91 insertions(+), 7 deletions(-)
 create mode 100644 src_assets/common/assets/web/configs/tabs/encoders/VAAPIEncoder.vue

diff --git a/docs/configuration.md b/docs/configuration.md
index 2b282d1c7a1..d5803037943 100644
--- a/docs/configuration.md
+++ b/docs/configuration.md
@@ -2303,6 +2303,33 @@ editing the `conf` file in a text editor. Use the examples as reference.
     </tr>
 </table>
 
+## VAAPI Encoder
+
+### vaapi_strict_rc_buffer
+
+<table>
+    <tr>
+        <td>Description</td>
+        <td colspan="2">
+            Enabling this option can avoid dropped frames over the network during scene changes, but video quality may
+            be reduced during motion.
+            @note{This option only applies when using Linux.}
+        </td>
+    </tr>
+    <tr>
+        <td>Default</td>
+        <td colspan="2">@code{}
+            disabled
+            @endcode</td>
+    </tr>
+    <tr>
+        <td>Example</td>
+        <td colspan="2">@code{}
+            vaapi_strict_rc_buffer = enabled
+            @endcode</td>
+    </tr>
+</table>
+
 ## Software Encoder
 
 ### sw_preset
diff --git a/src/config.cpp b/src/config.cpp
index 8475a5e3370..a61b69b96f1 100644
--- a/src/config.cpp
+++ b/src/config.cpp
@@ -377,6 +377,10 @@ namespace config {
       -1,
     },  // vt
 
+    {
+      false,  // strict_rc_buffer
+    },  // vaapi
+
     {},  // capture
     {},  // encoder
     {},  // adapter_name
@@ -1014,6 +1018,8 @@ namespace config {
     int_f(vars, "vt_software", video.vt.vt_require_sw, vt::force_software_from_view);
     int_f(vars, "vt_realtime", video.vt.vt_realtime, vt::rt_from_view);
 
+    bool_f(vars, "vaapi_strict_rc_buffer", video.vaapi.strict_rc_buffer);
+
     string_f(vars, "capture", video.capture);
     string_f(vars, "encoder", video.encoder);
     string_f(vars, "adapter_name", video.adapter_name);
diff --git a/src/config.h b/src/config.h
index e599afae454..891a4079772 100644
--- a/src/config.h
+++ b/src/config.h
@@ -71,6 +71,10 @@ namespace config {
       int vt_coder;
     } vt;
 
+    struct {
+      bool strict_rc_buffer;
+    } vaapi;
+
     std::string capture;
     std::string encoder;
     std::string adapter_name;
diff --git a/src/platform/linux/vaapi.cpp b/src/platform/linux/vaapi.cpp
index ada6370034a..b0f8cb670f3 100644
--- a/src/platform/linux/vaapi.cpp
+++ b/src/platform/linux/vaapi.cpp
@@ -131,11 +131,13 @@ namespace va {
 
     void
     init_codec_options(AVCodecContext *ctx, AVDictionary *options) override {
-      // Don't set the RC buffer size when using H.264 on Intel GPUs. It causes
-      // major encoding quality degradation.
-      auto vendor = vaQueryVendorString(va_display);
-      if (ctx->codec_id != AV_CODEC_ID_H264 || (vendor && !strstr(vendor, "Intel"))) {
-        ctx->rc_buffer_size = ctx->bit_rate * ctx->framerate.den / ctx->framerate.num;
+      if (config::video.vaapi.strict_rc_buffer) {
+        // Don't set the RC buffer size when using H.264 on Intel GPUs. It causes
+        // major encoding quality degradation.
+        auto vendor = vaQueryVendorString(va_display);
+        if (ctx->codec_id != AV_CODEC_ID_H264 || (vendor && !strstr(vendor, "Intel"))) {
+          ctx->rc_buffer_size = ctx->bit_rate * ctx->framerate.den / ctx->framerate.num;
+        }
       }
     }
 
diff --git a/src_assets/common/assets/web/config.html b/src_assets/common/assets/web/config.html
index c9c0a6ddf71..d247a9b4115 100644
--- a/src_assets/common/assets/web/config.html
+++ b/src_assets/common/assets/web/config.html
@@ -257,6 +257,13 @@ <h1 class="my-4">{{ $t('config.configuration') }}</h1>
               "vt_realtime": "enabled",
             },
           },
+          {
+            id: "vaapi",
+            name: "VAAPI Encoder",
+            options: {
+              "vaapi_strict_rc_buffer": "disabled",
+            },
+          },
           {
             id: "sw",
             name: "Software Encoder",
@@ -283,7 +290,7 @@ <h1 class="my-4">{{ $t('config.configuration') }}</h1>
           var app = document.getElementById("app");
           if (this.platform === "windows") {
             this.tabs = this.tabs.filter((el) => {
-              return el.id !== "vt";
+              return el.id !== "vt" && el.id !== "vaapi";
             });
           }
           if (this.platform === "linux") {
@@ -293,7 +300,7 @@ <h1 class="my-4">{{ $t('config.configuration') }}</h1>
           }
           if (this.platform === "macos") {
             this.tabs = this.tabs.filter((el) => {
-              return el.id !== "amd" && el.id !== "nv" && el.id !== "qsv";
+              return el.id !== "amd" && el.id !== "nv" && el.id !== "qsv" && el.id !== "vaapi";
             });
           }
 
diff --git a/src_assets/common/assets/web/configs/tabs/ContainerEncoders.vue b/src_assets/common/assets/web/configs/tabs/ContainerEncoders.vue
index 084c3001f57..1dce1403adf 100644
--- a/src_assets/common/assets/web/configs/tabs/ContainerEncoders.vue
+++ b/src_assets/common/assets/web/configs/tabs/ContainerEncoders.vue
@@ -5,6 +5,7 @@ import IntelQuickSyncEncoder from './encoders/IntelQuickSyncEncoder.vue'
 import AmdAmfEncoder from './encoders/AmdAmfEncoder.vue'
 import VideotoolboxEncoder from './encoders/VideotoolboxEncoder.vue'
 import SoftwareEncoder from './encoders/SoftwareEncoder.vue'
+import VAAPIEncoder from './encoders/VAAPIEncoder.vue'
 
 const props = defineProps([
   'platform',
@@ -45,6 +46,13 @@ const config = ref(props.config)
       :config="config"
   />
 
+  <!-- VAAPI Encoder Tab -->
+  <VAAPIEncoder
+      v-if="currentTab === 'vaapi'"
+      :platform="platform"
+      :config="config"
+  />
+
   <!-- Software Encoder Tab -->
   <SoftwareEncoder
       v-if="currentTab === 'sw'"
diff --git a/src_assets/common/assets/web/configs/tabs/encoders/VAAPIEncoder.vue b/src_assets/common/assets/web/configs/tabs/encoders/VAAPIEncoder.vue
new file mode 100644
index 00000000000..8f4425d4d07
--- /dev/null
+++ b/src_assets/common/assets/web/configs/tabs/encoders/VAAPIEncoder.vue
@@ -0,0 +1,28 @@
+<script setup>
+import { ref } from 'vue'
+
+const props = defineProps([
+  'platform',
+  'config',
+])
+
+const config = ref(props.config)
+</script>
+
+<template>
+  <div id="vaapi-encoder" class="config-page">
+    <!-- Strict RC Buffer -->
+    <div class="mb-3">
+      <label for="vaapi_strict_rc_buffer" class="form-label">{{ $t('config.vaapi_strict_rc_buffer') }}</label>
+      <select id="vaapi_strict_rc_buffer" class="form-select" v-model="config.vaapi_strict_rc_buffer">
+        <option value="enabled">{{ $t('_common.enabled') }}</option>
+        <option value="disabled">{{ $t('_common.disabled') }}</option>
+      </select>
+      <div class="form-text">{{ $t('config.vaapi_strict_rc_buffer_desc') }}</div>
+    </div>
+  </div>
+</template>
+
+<style scoped>
+
+</style>
diff --git a/src_assets/common/assets/web/public/assets/locale/en.json b/src_assets/common/assets/web/public/assets/locale/en.json
index 12844fcf874..a0d4250f80a 100644
--- a/src_assets/common/assets/web/public/assets/locale/en.json
+++ b/src_assets/common/assets/web/public/assets/locale/en.json
@@ -310,6 +310,8 @@
     "touchpad_as_ds4_desc": "If disabled, touchpad presence will not be taken into account during gamepad type selection.",
     "upnp": "UPnP",
     "upnp_desc": "Automatically configure port forwarding for streaming over the Internet",
+    "vaapi_strict_rc_buffer": "Strictly enforce frame bitrate limits",
+    "vaapi_strict_rc_buffer_desc": "Enabling this option can avoid dropped frames over the network during scene changes, but video quality may be reduced during motion.",
     "virtual_sink": "Virtual Sink",
     "virtual_sink_desc": "Manually specify a virtual audio device to use. If unset, the device is chosen automatically. We strongly recommend leaving this field blank to use automatic device selection!",
     "virtual_sink_placeholder": "Steam Streaming Speakers",