lavfi: add vsink_buffer, and use it in ff* tools

Also add the public interface libavfilter/vsink_buffer.h.

5 files changed, 162 insertions, 2 deletions

diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index c594573798..84a7ac3394 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -6,7 +6,7 @@ FFLIBS-$(CONFIG_MOVIE_FILTER) += avformat avcodec
 FFLIBS-$(CONFIG_SCALE_FILTER) += swscale
 FFLIBS-$(CONFIG_MP_FILTER) += avcodec
 
-HEADERS = avcodec.h avfilter.h avfiltergraph.h vsrc_buffer.h
+HEADERS = avcodec.h avfilter.h avfiltergraph.h vsink_buffer.hvsrc_buffer.h
 
 OBJS = allfilters.o                                                     \
        avfilter.o                                                       \
@@ -69,6 +69,7 @@ OBJS-$(CONFIG_FREI0R_SRC_FILTER)             += vf_frei0r.o
 OBJS-$(CONFIG_MOVIE_FILTER)                  += vsrc_movie.o
 OBJS-$(CONFIG_NULLSRC_FILTER)                += vsrc_nullsrc.o
 
+OBJS-$(CONFIG_BUFFERSINK_FILTER)             += vsink_buffer.o
 OBJS-$(CONFIG_NULLSINK_FILTER)               += vsink_nullsink.o
 
 
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 2983f6bd8c..42047ecbe8 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -85,5 +85,6 @@ void avfilter_register_all(void)
     REGISTER_FILTER (MOVIE,       movie,       vsrc);
     REGISTER_FILTER (NULLSRC,     nullsrc,     vsrc);
 
+    REGISTER_FILTER (BUFFER,      buffersink,  vsink);
     REGISTER_FILTER (NULLSINK,    nullsink,    vsink);
 }
diff --git a/libavfilter/avfilter.h b/libavfilter/avfilter.h
index bcfc4c6df9..5ac70399ac 100644
--- a/libavfilter/avfilter.h
+++ b/libavfilter/avfilter.h
@@ -26,7 +26,7 @@
 #include "libavutil/samplefmt.h"
 
 #define LIBAVFILTER_VERSION_MAJOR  2
-#define LIBAVFILTER_VERSION_MINOR 20
+#define LIBAVFILTER_VERSION_MINOR 21
 #define LIBAVFILTER_VERSION_MICRO  0
 
 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
diff --git a/libavfilter/vsink_buffer.c b/libavfilter/vsink_buffer.c
new file mode 100644
index 0000000000..c0824606a9
--- /dev/null
+++ b/libavfilter/vsink_buffer.c
@@ -0,0 +1,111 @@
+/*
+ * Copyright (c) 2011 Stefano Sabatini
+ *
+ * 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
+ */
+
+/**
+ * @file
+ * buffer video sink
+ */
+
+#include "avfilter.h"
+#include "vsink_buffer.h"
+
+typedef struct {
+    AVFilterBufferRef *picref;   ///< cached picref
+    enum PixelFormat *pix_fmts;  ///< accepted pixel formats, must be terminated with -1
+} BufferSinkContext;
+
+static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
+{
+    BufferSinkContext *buf = ctx->priv;
+
+    if (!opaque) {
+        av_log(ctx, AV_LOG_ERROR, "No opaque field provided, which is required.\n");
+        return AVERROR(EINVAL);
+    }
+
+    buf->pix_fmts = opaque;
+    return 0;
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+    BufferSinkContext *buf = ctx->priv;
+
+    if (buf->picref)
+        avfilter_unref_buffer(buf->picref);
+    buf->picref = NULL;
+}
+
+static void end_frame(AVFilterLink *inlink)
+{
+    BufferSinkContext *buf = inlink->dst->priv;
+
+    if (buf->picref)            /* drop the last cached frame */
+        avfilter_unref_buffer(buf->picref);
+    buf->picref = inlink->cur_buf;
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+    BufferSinkContext *buf = ctx->priv;
+
+    avfilter_set_common_formats(ctx, avfilter_make_format_list(buf->pix_fmts));
+    return 0;
+}
+
+int av_vsink_buffer_get_video_buffer_ref(AVFilterContext *ctx,
+                                         AVFilterBufferRef **picref, int flags)
+{
+    BufferSinkContext *buf = ctx->priv;
+    AVFilterLink *inlink = ctx->inputs[0];
+    int ret;
+    *picref = NULL;
+
+    /* no picref available, fetch it from the filterchain */
+    if (!buf->picref) {
+        if ((ret = avfilter_request_frame(inlink)) < 0)
+            return ret;
+    }
+
+    if (!buf->picref)
+        return AVERROR(EINVAL);
+
+    *picref = buf->picref;
+    if (!(flags & AV_VSINK_BUF_FLAG_PEEK))
+        buf->picref = NULL;
+
+    return 0;
+}
+
+AVFilter avfilter_vsink_buffersink = {
+    .name      = "buffersink",
+    .priv_size = sizeof(BufferSinkContext),
+    .init      = init,
+    .uninit    = uninit,
+
+    .query_formats = query_formats,
+
+    .inputs    = (AVFilterPad[]) {{ .name          = "default",
+                                    .type          = AVMEDIA_TYPE_VIDEO,
+                                    .end_frame     = end_frame,
+                                    .min_perms     = AV_PERM_READ, },
+                                  { .name = NULL }},
+    .outputs   = (AVFilterPad[]) {{ .name = NULL }},
+};
diff --git a/libavfilter/vsink_buffer.h b/libavfilter/vsink_buffer.h
new file mode 100644
index 0000000000..88b4c1d258
--- /dev/null
+++ b/libavfilter/vsink_buffer.h
@@ -0,0 +1,47 @@
+/*
+ * 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
+ */
+
+#ifndef AVFILTER_VSINK_BUFFER_H
+#define AVFILTER_VSINK_BUFFER_H
+
+/**
+ * @file
+ * memory buffer sink API for video
+ */
+
+#include "avfilter.h"
+
+/**
+ * Tell av_vsink_buffer_get_video_buffer_ref() to read the picref, but not
+ * remove it from the buffer. This is useful if you need only to read
+ * the picref, without to fetch it.
+ */
+#define AV_VSINK_BUF_FLAG_PEEK 1
+
+/**
+ * Get a video buffer data from buffer_sink and put it in picref.
+ *
+ * @param buffer_sink pointer to a buffer sink context
+ * @param flags a combination of AV_VSINK_BUF_FLAG_* flags
+ * @return >= 0 in case of success, a negative AVERROR code in case of
+ * failure
+ */
+int av_vsink_buffer_get_video_buffer_ref(AVFilterContext *buffer_sink,
+                                         AVFilterBufferRef **picref, int flags);
+
+#endif /* AVFILTER_VSINK_BUFFER_H */