[FFmpeg-devel] [PATCH] avfilter: add sdlvsink for video display

[Shiqi Zhu]

Signed-off-by: Shiqi Zhu <hiccupzhu at gmail.com>
---
 configure                    |   1 +
 libavfilter/Makefile         |   1 +
 libavfilter/allfilters.c     |   1 +
 libavfilter/vsink_sdlvsink.c | 142 +++++++++++++++++++++++++++++++++++
 4 files changed, 145 insertions(+)
 create mode 100644 libavfilter/vsink_sdlvsink.c

diff --git a/configure b/configure
index 6c5b8aab9a..968b5c8912 100755
--- a/configure
+++ b/configure
@@ -3977,6 +3977,7 @@ xstack_qsv_filter_deps="libmfx"
 xstack_qsv_filter_select="qsvvpp"
 pad_vaapi_filter_deps="vaapi_1"
 drawbox_vaapi_filter_deps="vaapi_1"
+sdlvsink_filter_deps="sdl2"
 
 # examples
 avio_http_serve_files_deps="avformat avutil fork"
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 5992fd161f..feac6b464d 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -616,6 +616,7 @@ OBJS-$(CONFIG_YUVTESTSRC_FILTER)             += vsrc_testsrc.o
 OBJS-$(CONFIG_ZONEPLATE_FILTER)              += vsrc_testsrc.o
 
 OBJS-$(CONFIG_NULLSINK_FILTER)               += vsink_nullsink.o
+OBJS-$(CONFIG_SDLVSINK_FILTER)               += vsink_sdlvsink.o
 
 # multimedia filters
 OBJS-$(CONFIG_A3DSCOPE_FILTER)               += avf_a3dscope.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index c532682fc2..d5f942ffb5 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -579,6 +579,7 @@ extern const AVFilter ff_vsrc_yuvtestsrc;
 extern const AVFilter ff_vsrc_zoneplate;
 
 extern const AVFilter ff_vsink_nullsink;
+extern const AVFilter ff_vsink_sdlvsink;
 
 /* multimedia filters */
 extern const AVFilter ff_avf_a3dscope;
diff --git a/libavfilter/vsink_sdlvsink.c b/libavfilter/vsink_sdlvsink.c
new file mode 100644
index 0000000000..630f719c7e
--- /dev/null
+++ b/libavfilter/vsink_sdlvsink.c
@@ -0,0 +1,142 @@
+/*
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "avfilter.h"
+#include "internal.h"
+#include "libavutil/internal.h"
+#include <SDL2/SDL.h>
+#include <unistd.h>
+
+typedef struct {
+    SDL_Window   *window;
+    SDL_Renderer *render;
+    SDL_Texture  *texture;
+} SDLVideoContext;
+
+static int init(AVFilterContext *ctx)
+{
+    if (SDL_Init(SDL_INIT_VIDEO) < 0)
+    {
+        av_log(ctx, AV_LOG_ERROR, "SDL2 could not initialize! %s\n", SDL_GetError());
+        return -ENOMEM;
+    }
+
+    SDL_PollEvent(NULL);
+    SDL_SetHint(SDL_HINT_VIDEO_X11_NET_WM_BYPASS_COMPOSITOR, "0");
+
+    return 0;
+}
+
+static void uninit(AVFilterContext *ctx)
+{
+    SDLVideoContext *sink = ctx->priv;
+    
+    if (sink->texture) {
+        SDL_DestroyTexture(sink->texture);
+        sink->texture = NULL;
+    }
+
+    if (sink->render) {
+        SDL_DestroyRenderer(sink->render);
+        sink->render = NULL;
+    }
+
+    if (sink->window) {
+        SDL_DestroyWindow(sink->window);
+        sink->window = NULL;
+    }
+
+    SDL_Quit();
+}
+
+static int filter_frame(AVFilterLink *link, AVFrame *frame)
+{
+    AVFilterContext *ctx = link->dst;
+    SDLVideoContext *sink = ctx->priv;
+    SDL_RendererInfo renderer_info;
+
+    if (!sink->window) {
+        sink->window = SDL_CreateWindow("YUV Player",
+                                         SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
+                                         frame->width, frame->height, SDL_WINDOW_SHOWN | SDL_WINDOW_RESIZABLE);
+        if (!sink->window) {
+            av_log(ctx, AV_LOG_ERROR, "SDL2 could not create window %s\n", SDL_GetError());
+            return -ENOMEM;
+        }
+    }
+
+    if (!sink->render) {
+        sink->render = SDL_CreateRenderer(sink->window, -1, 0);
+        if (!sink->render) {
+            av_log(ctx, AV_LOG_ERROR, "SDL2 could not create render %s\n", SDL_GetError());
+            return -ENOMEM;
+        }
+        SDL_SetHint(SDL_HINT_RENDER_SCALE_QUALITY, "linear");
+
+        SDL_GetRendererInfo(sink->render, &renderer_info);
+        av_log(ctx, AV_LOG_INFO, "sdl2 renderer name:%s\n", renderer_info.name);
+    }
+    
+    if (!sink->texture) {
+        sink->texture = SDL_CreateTexture(sink->render, SDL_PIXELFORMAT_IYUV,
+                                           SDL_TEXTUREACCESS_STREAMING, frame->width, frame->height);
+        if (!sink->texture) {
+            av_log(ctx, AV_LOG_ERROR, "create texture failed %s\n", SDL_GetError());
+            return -EINVAL;
+        }
+    }
+
+    SDL_UpdateYUVTexture(sink->texture, NULL,
+                         frame->data[0], frame->linesize[0],
+                         frame->data[1], frame->linesize[1],
+                         frame->data[2], frame->linesize[2]);
+
+    SDL_RenderClear(sink->render);
+
+    SDL_RenderCopy(sink->render, sink->texture, NULL, NULL);
+    SDL_RenderPresent(sink->render);
+
+    av_frame_free(&frame);
+
+    return 0;
+}
+
+static const AVFilterPad avfilter_vsink_sdlvsink_inputs[] = {
+    {
+        .name        = "default",
+        .type        = AVMEDIA_TYPE_VIDEO,
+        .filter_frame = filter_frame,
+    },
+};
+
+static const AVFilterPad avfilter_vsink_sdlvsink_outputs[] = {
+    {
+        .name = NULL,
+        .type = AVMEDIA_TYPE_VIDEO,
+    },
+};
+
+const AVFilter ff_vsink_sdlvsink = {
+    .name        = "sdlvsink",
+    .description = NULL_IF_CONFIG_SMALL("Do absolutely nothing with the input video."),
+    .priv_size   = sizeof(SDLVideoContext),
+    .init        = init,
+    .uninit      = uninit,
+    FILTER_INPUTS(avfilter_vsink_sdlvsink_inputs),
+    FILTER_OUTPUTS(avfilter_vsink_sdlvsink_outputs),
+};
-- 
2.34.1