Add format and noformat filters.

Originally committed as revision 20390 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 154 insertions, 0 deletions

diff --git a/libavfilter/vf_format.c b/libavfilter/vf_format.c
new file mode 100644
index 0000000000..1552848344
--- /dev/null
+++ b/libavfilter/vf_format.c
@@ -0,0 +1,154 @@
+/*
+ * copyright (c) 2007 Bobby Bingham
+ *
+ * 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 libavfilter/vf_format.c
+ * video format and noformat filters
+ */
+
+#include "avfilter.h"
+
+typedef struct {
+    /**
+     * List of flags telling if a given image format has been listed
+     * as argument to the filter.
+     */
+    int listed_pix_fmt_flags[PIX_FMT_NB];
+} FormatContext;
+
+#define PIX_FMT_NAME_MAXSIZE 32
+
+static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
+{
+    FormatContext *format = ctx->priv;
+    const char *cur, *sep;
+    char             pix_fmt_name[PIX_FMT_NAME_MAXSIZE];
+    int              pix_fmt_name_len;
+    enum PixelFormat pix_fmt;
+
+    /* parse the list of formats */
+    for (cur = args; cur; cur = sep ? sep+1 : NULL) {
+        if (!(sep = strchr(cur, ':')))
+            pix_fmt_name_len = strlen(cur);
+        else
+            pix_fmt_name_len = sep - cur;
+        if (pix_fmt_name_len >= PIX_FMT_NAME_MAXSIZE) {
+            av_log(ctx, AV_LOG_ERROR, "Format name too long\n");
+            return -1;
+        }
+
+        memcpy(pix_fmt_name, cur, pix_fmt_name_len);
+        pix_fmt_name[pix_fmt_name_len] = 0;
+        pix_fmt = avcodec_get_pix_fmt(pix_fmt_name);
+
+        if (pix_fmt == PIX_FMT_NONE) {
+            av_log(ctx, AV_LOG_ERROR, "Unknown pixel format: %s\n", pix_fmt_name);
+            return -1;
+        }
+
+        format->listed_pix_fmt_flags[pix_fmt] = 1;
+    }
+
+    return 0;
+}
+
+static AVFilterFormats *make_format_list(FormatContext *format, int flag)
+{
+    AVFilterFormats *formats;
+    enum PixelFormat pix_fmt;
+
+    formats = av_mallocz(sizeof(AVFilterFormats));
+    formats->formats = av_malloc(sizeof(enum PixelFormat) * PIX_FMT_NB);
+
+    for (pix_fmt = 0; pix_fmt < PIX_FMT_NB; pix_fmt++)
+        if (format->listed_pix_fmt_flags[pix_fmt] == flag)
+            formats->formats[formats->format_count++] = pix_fmt;
+
+    return formats;
+}
+
+static int query_formats_format(AVFilterContext *ctx)
+{
+    avfilter_set_common_formats(ctx, make_format_list(ctx->priv, 1));
+    return 0;
+}
+
+static int query_formats_noformat(AVFilterContext *ctx)
+{
+    avfilter_set_common_formats(ctx, make_format_list(ctx->priv, 0));
+    return 0;
+}
+
+static void start_frame(AVFilterLink *link, AVFilterPicRef *picref)
+{
+    avfilter_start_frame(link->dst->outputs[0], picref);
+}
+
+static void end_frame(AVFilterLink *link)
+{
+    avfilter_end_frame(link->dst->outputs[0]);
+}
+
+static void draw_slice(AVFilterLink *link, int y, int h)
+{
+    avfilter_draw_slice(link->dst->outputs[0], y, h);
+}
+
+AVFilter avfilter_vf_format = {
+    .name      = "format",
+    .description = "Convert the input video to one of the specified pixel formats.",
+
+    .init      = init,
+
+    .query_formats = query_formats_format,
+
+    .priv_size = sizeof(FormatContext),
+
+    .inputs    = (AVFilterPad[]) {{ .name            = "default",
+                                    .type            = CODEC_TYPE_VIDEO,
+                                    .start_frame     = start_frame,
+                                    .draw_slice      = draw_slice,
+                                    .end_frame       = end_frame, },
+                                  { .name = NULL}},
+    .outputs   = (AVFilterPad[]) {{ .name            = "default",
+                                    .type            = CODEC_TYPE_VIDEO },
+                                  { .name = NULL}},
+};
+
+AVFilter avfilter_vf_noformat = {
+    .name      = "noformat",
+    .description = "Force libavfilter not to use any of the specified pixel formats as the input to the next filter.",
+
+    .init      = init,
+
+    .query_formats = query_formats_noformat,
+
+    .priv_size = sizeof(FormatContext),
+
+    .inputs    = (AVFilterPad[]) {{ .name            = "default",
+                                    .type            = CODEC_TYPE_VIDEO,
+                                    .start_frame     = start_frame,
+                                    .draw_slice      = draw_slice,
+                                    .end_frame       = end_frame, },
+                                  { .name = NULL}},
+    .outputs   = (AVFilterPad[]) {{ .name            = "default",
+                                    .type            = CODEC_TYPE_VIDEO },
+                                  { .name = NULL}},
+};