4 files changed, 103 insertions, 4 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 561eaafb2..7276ac9dd 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -453,6 +453,7 @@ endif()
 # List of all FFmpeg components required
 set(FFmpeg_COMPONENTS
     avcodec
+    avfilter
     avutil
     swscale)
 
diff --git a/externals/ffmpeg/CMakeLists.txt b/externals/ffmpeg/CMakeLists.txt
index 0baac8e17..03fad0778 100644
--- a/externals/ffmpeg/CMakeLists.txt
+++ b/externals/ffmpeg/CMakeLists.txt
@@ -131,7 +131,6 @@ if (NOT WIN32)
         COMMAND
             /bin/bash ${FFmpeg_PREFIX}/configure
                 --disable-avdevice
-                --disable-avfilter
                 --disable-avformat
                 --disable-doc
                 --disable-everything
@@ -143,6 +142,7 @@ if (NOT WIN32)
                 --enable-decoder=h264
                 --enable-decoder=vp8
                 --enable-decoder=vp9
+                --enable-filter=yadif
                 --cc="${FFmpeg_CC}"
                 --cxx="${FFmpeg_CXX}"
                 ${FFmpeg_HWACCEL_FLAGS}
@@ -199,7 +199,7 @@ if (NOT WIN32)
     endif()
 else(WIN32)
     # Use yuzu FFmpeg binaries
-    set(FFmpeg_EXT_NAME "ffmpeg-4.4")
+    set(FFmpeg_EXT_NAME "ffmpeg-5.1.3")
     set(FFmpeg_PATH "${CMAKE_BINARY_DIR}/externals/${FFmpeg_EXT_NAME}")
     download_bundled_external("ffmpeg/" ${FFmpeg_EXT_NAME} "")
     set(FFmpeg_FOUND YES)
@@ -210,6 +210,7 @@ else(WIN32)
     set(FFmpeg_LIBRARIES
     ${FFmpeg_LIBRARY_DIR}/swscale.lib
     ${FFmpeg_LIBRARY_DIR}/avcodec.lib
+    ${FFmpeg_LIBRARY_DIR}/avfilter.lib
     ${FFmpeg_LIBRARY_DIR}/avutil.lib
     CACHE PATH "Paths to FFmpeg libraries" FORCE)
     # exported variables
diff --git a/src/video_core/host1x/codecs/codec.cpp b/src/video_core/host1x/codecs/codec.cpp
index 3e9022dce..cd6a3a9b8 100644
--- a/src/video_core/host1x/codecs/codec.cpp
+++ b/src/video_core/host1x/codecs/codec.cpp
@@ -5,6 +5,7 @@
 #include <fstream>
 #include <vector>
 #include "common/assert.h"
+#include "common/scope_exit.h"
 #include "common/settings.h"
 #include "video_core/host1x/codecs/codec.h"
 #include "video_core/host1x/codecs/h264.h"
@@ -14,6 +15,8 @@
 #include "video_core/memory_manager.h"
 
 extern "C" {
+#include <libavfilter/buffersink.h>
+#include <libavfilter/buffersrc.h>
 #include <libavutil/opt.h>
 #ifdef LIBVA_FOUND
 // for querying VAAPI driver information
@@ -85,6 +88,10 @@ Codec::~Codec() {
     // Free libav memory
     avcodec_free_context(&av_codec_ctx);
     av_buffer_unref(&av_gpu_decoder);
+
+    if (filters_initialized) {
+        avfilter_graph_free(&av_filter_graph);
+    }
 }
 
 bool Codec::CreateGpuAvDevice() {
@@ -167,6 +174,62 @@ void Codec::InitializeGpuDecoder() {
     av_codec_ctx->get_format = GetGpuFormat;
 }
 
+void Codec::InitializeAvFilters(AVFrame* frame) {
+    const AVFilter* buffer_src = avfilter_get_by_name("buffer");
+    const AVFilter* buffer_sink = avfilter_get_by_name("buffersink");
+    AVFilterInOut* inputs = avfilter_inout_alloc();
+    AVFilterInOut* outputs = avfilter_inout_alloc();
+    SCOPE_EXIT({
+        avfilter_inout_free(&inputs);
+        avfilter_inout_free(&outputs);
+    });
+
+    // Don't know how to get the accurate time_base but it doesn't matter for yadif filter
+    // so just use 1/1 to make buffer filter happy
+    std::string args = fmt::format("video_size={}x{}:pix_fmt={}:time_base=1/1", frame->width,
+                                   frame->height, frame->format);
+
+    av_filter_graph = avfilter_graph_alloc();
+    int ret = avfilter_graph_create_filter(&av_filter_src_ctx, buffer_src, "in", args.c_str(),
+                                           nullptr, av_filter_graph);
+    if (ret < 0) {
+        LOG_ERROR(Service_NVDRV, "avfilter_graph_create_filter source error: {}", ret);
+        return;
+    }
+
+    ret = avfilter_graph_create_filter(&av_filter_sink_ctx, buffer_sink, "out", nullptr, nullptr,
+                                       av_filter_graph);
+    if (ret < 0) {
+        LOG_ERROR(Service_NVDRV, "avfilter_graph_create_filter sink error: {}", ret);
+        return;
+    }
+
+    inputs->name = av_strdup("out");
+    inputs->filter_ctx = av_filter_sink_ctx;
+    inputs->pad_idx = 0;
+    inputs->next = nullptr;
+
+    outputs->name = av_strdup("in");
+    outputs->filter_ctx = av_filter_src_ctx;
+    outputs->pad_idx = 0;
+    outputs->next = nullptr;
+
+    const char* description = "yadif=1:-1:0";
+    ret = avfilter_graph_parse_ptr(av_filter_graph, description, &inputs, &outputs, nullptr);
+    if (ret < 0) {
+        LOG_ERROR(Service_NVDRV, "avfilter_graph_parse_ptr error: {}", ret);
+        return;
+    }
+
+    ret = avfilter_graph_config(av_filter_graph, nullptr);
+    if (ret < 0) {
+        LOG_ERROR(Service_NVDRV, "avfilter_graph_config error: {}", ret);
+        return;
+    }
+
+    filters_initialized = true;
+}
+
 void Codec::Initialize() {
     const AVCodecID codec = [&] {
         switch (current_codec) {
@@ -271,8 +334,34 @@ void Codec::Decode() {
         UNIMPLEMENTED_MSG("Unexpected video format: {}", final_frame->format);
         return;
     }
-    av_frames.push(std::move(final_frame));
-    if (av_frames.size() > 10) {
+    if (!final_frame->interlaced_frame) {
+        av_frames.push(std::move(final_frame));
+    } else {
+        if (!filters_initialized) {
+            InitializeAvFilters(final_frame.get());
+        }
+        if (const int ret = av_buffersrc_add_frame_flags(av_filter_src_ctx, final_frame.get(),
+                                                         AV_BUFFERSRC_FLAG_KEEP_REF);
+            ret) {
+            LOG_DEBUG(Service_NVDRV, "av_buffersrc_add_frame_flags error {}", ret);
+            return;
+        }
+        while (true) {
+            auto filter_frame = AVFramePtr{av_frame_alloc(), AVFrameDeleter};
+
+            int ret = av_buffersink_get_frame(av_filter_sink_ctx, filter_frame.get());
+
+            if (ret == AVERROR(EAGAIN) || ret == AVERROR(AVERROR_EOF))
+                break;
+            if (ret < 0) {
+                LOG_DEBUG(Service_NVDRV, "av_buffersink_get_frame error {}", ret);
+                return;
+            }
+
+            av_frames.push(std::move(filter_frame));
+        }
+    }
+    while (av_frames.size() > 10) {
         LOG_TRACE(Service_NVDRV, "av_frames.push overflow dropped frame");
         av_frames.pop();
     }
diff --git a/src/video_core/host1x/codecs/codec.h b/src/video_core/host1x/codecs/codec.h
index 0d45fb7fe..06fe00a4b 100644
--- a/src/video_core/host1x/codecs/codec.h
+++ b/src/video_core/host1x/codecs/codec.h
@@ -15,6 +15,7 @@ extern "C" {
 #pragma GCC diagnostic ignored "-Wconversion"
 #endif
 #include <libavcodec/avcodec.h>
+#include <libavfilter/avfilter.h>
 #if defined(__GNUC__) || defined(__clang__)
 #pragma GCC diagnostic pop
 #endif
@@ -61,17 +62,24 @@ public:
 private:
     void InitializeAvCodecContext();
 
+    void InitializeAvFilters(AVFrame* frame);
+
     void InitializeGpuDecoder();
 
     bool CreateGpuAvDevice();
 
     bool initialized{};
+    bool filters_initialized{};
     Host1x::NvdecCommon::VideoCodec current_codec{Host1x::NvdecCommon::VideoCodec::None};
 
     const AVCodec* av_codec{nullptr};
     AVCodecContext* av_codec_ctx{nullptr};
     AVBufferRef* av_gpu_decoder{nullptr};
 
+    AVFilterContext* av_filter_src_ctx{nullptr};
+    AVFilterContext* av_filter_sink_ctx{nullptr};
+    AVFilterGraph* av_filter_graph{nullptr};
+
     Host1x::Host1x& host1x;
     const Host1x::NvdecCommon::NvdecRegisters& state;
     std::unique_ptr<Decoder::H264> h264_decoder;