[PATCH 2/4] Add transpose filter.

Stefano Sabatini stefano.sabatini-lala
Mon Oct 11 14:16:35 CEST 2010


---
 doc/filters.texi           |   35 +++++++
 libavfilter/Makefile       |    1 +
 libavfilter/allfilters.c   |    1 +
 libavfilter/vf_transpose.c |  211 ++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 248 insertions(+), 0 deletions(-)
 create mode 100644 libavfilter/vf_transpose.c

diff --git a/doc/filters.texi b/doc/filters.texi
index 66c1606..f6b262b 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -508,6 +508,41 @@ not specified it will use the default value of 16.
 Adding this in the beginning of filter chains should make filtering
 faster due to better use of the memory cache.
 
+ at section transpose
+
+Transpose rows with columns in the input video and optionally flip it.
+
+It accepts a parameter representing an integer, which can assume the
+values:
+
+0    Rotate by 90 degrees clockwise and vertically flip (default), that is:
+ at example
+L.R     r.R
+. . ->  . .
+l.r     l.L
+ at end example
+
+1    Rotate by 90 degrees clockwise, that is:
+ at example
+L.R     l.L
+. . ->  . .
+l.r     r.R
+ at end example
+
+2    Rotate by 90 degrees counterclockwise, that is:
+ at example
+L.R     R.r
+. . ->  . .
+l.r     L.l
+ at end example
+
+3    Rotate by 90 degrees counterclockwise and vertically flip, that is:
+ at example
+L.R     L.l
+. . ->  . .
+l.r     R.r
+ at end example
+
 @section unsharp
 
 Sharpen or blur the input video.
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index a00c1a2..38d2762 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -38,6 +38,7 @@ OBJS-$(CONFIG_PIXELASPECT_FILTER)            += vf_aspect.o
 OBJS-$(CONFIG_SCALE_FILTER)                  += vf_scale.o
 OBJS-$(CONFIG_SETTB_FILTER)                  += vf_settb.o
 OBJS-$(CONFIG_SLICIFY_FILTER)                += vf_slicify.o
+OBJS-$(CONFIG_TRANSPOSE_FILTER)              += vf_transpose.o
 OBJS-$(CONFIG_UNSHARP_FILTER)                += vf_unsharp.o
 OBJS-$(CONFIG_VFLIP_FILTER)                  += vf_vflip.o
 OBJS-$(CONFIG_YADIF_FILTER)                  += vf_yadif.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index ae4a32d..bade1dd 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -58,6 +58,7 @@ void avfilter_register_all(void)
     REGISTER_FILTER (SCALE,       scale,       vf);
     REGISTER_FILTER (SETTB,       settb,       vf);
     REGISTER_FILTER (SLICIFY,     slicify,     vf);
+    REGISTER_FILTER (TRANSPOSE,   transpose,   vf);
     REGISTER_FILTER (UNSHARP,     unsharp,     vf);
     REGISTER_FILTER (VFLIP,       vflip,       vf);
     REGISTER_FILTER (YADIF,       yadif,       vf);
diff --git a/libavfilter/vf_transpose.c b/libavfilter/vf_transpose.c
new file mode 100644
index 0000000..94737be
--- /dev/null
+++ b/libavfilter/vf_transpose.c
@@ -0,0 +1,211 @@
+/*
+ * Copyright (C) 2010 Stefano Sabatini
+ * Copyright (C) 2008 Vitor Sessak
+ *
+ * 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
+ * transposition filter
+ */
+
+#include "libavutil/intreadwrite.h"
+#include "libavutil/pixdesc.h"
+#include "libavcore/imgutils.h"
+#include "avfilter.h"
+
+typedef struct {
+    int hsub, vsub;
+    int pixsteps[4];
+
+    /* 0    Rotate by 90 degrees clockwise and flip (default). */
+    /* 1    Rotate by 90 degrees clockwise.                    */
+    /* 2    Rotate by 90 degrees counterclockwise.             */
+    /* 3    Rotate by 90 degrees counterclockwise and flip.    */
+    int dir;
+} TransContext;
+
+static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
+{
+    TransContext *trans = ctx->priv;
+    trans->dir = 0;
+
+    if (args)
+        sscanf(args, "%d", &trans->dir);
+
+    if (trans->dir < 0 || trans->dir > 3) {
+        av_log(ctx, AV_LOG_ERROR, "Invalid value %d not between 0 and 3.\n",
+               trans->dir);
+        return AVERROR(EINVAL);
+    }
+    return 0;
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+    enum PixelFormat pix_fmts[] = {
+        PIX_FMT_ARGB,         PIX_FMT_RGBA,
+        PIX_FMT_ABGR,         PIX_FMT_BGRA,
+        PIX_FMT_RGB24,        PIX_FMT_BGR24,
+        PIX_FMT_RGB565BE,     PIX_FMT_RGB565LE,
+        PIX_FMT_RGB555BE,     PIX_FMT_RGB555LE,
+        PIX_FMT_BGR565BE,     PIX_FMT_BGR565LE,
+        PIX_FMT_BGR555BE,     PIX_FMT_BGR555LE,
+        PIX_FMT_GRAY16BE,     PIX_FMT_GRAY16LE,
+        PIX_FMT_YUV420P16LE,  PIX_FMT_YUV420P16BE,
+        PIX_FMT_YUV422P16LE,  PIX_FMT_YUV422P16BE,
+        PIX_FMT_YUV444P16LE,  PIX_FMT_YUV444P16BE,
+        PIX_FMT_NV12,         PIX_FMT_NV21,
+        PIX_FMT_RGB8,         PIX_FMT_BGR8,
+        PIX_FMT_RGB4_BYTE,    PIX_FMT_BGR4_BYTE,
+        PIX_FMT_YUV444P,      PIX_FMT_YUV422P,
+        PIX_FMT_YUV420P,      PIX_FMT_YUVJ420P,
+        PIX_FMT_YUV411P,      PIX_FMT_YUV410P,
+        PIX_FMT_YUVJ444P,     PIX_FMT_YUVJ422P,
+        PIX_FMT_YUV440P,      PIX_FMT_YUVJ440P,
+        PIX_FMT_YUVA420P,     PIX_FMT_GRAY8,
+        PIX_FMT_NONE
+    };
+
+    avfilter_set_common_formats(ctx, avfilter_make_format_list(pix_fmts));
+    return 0;
+}
+
+static int config_props_output(AVFilterLink *outlink)
+{
+    AVFilterContext *ctx = outlink->src;
+    TransContext *trans = ctx->priv;
+    AVFilterLink *inlink = ctx->inputs[0];
+    const AVPixFmtDescriptor *pixdesc = &av_pix_fmt_descriptors[outlink->format];
+
+    trans->hsub = av_pix_fmt_descriptors[inlink->format].log2_chroma_w;
+    trans->vsub = av_pix_fmt_descriptors[inlink->format].log2_chroma_h;
+
+    av_image_fill_max_pixsteps(trans->pixsteps, NULL, pixdesc);
+
+    outlink->w = inlink->h;
+    outlink->h = inlink->w;
+
+    av_log(ctx, AV_LOG_INFO, "w:%d h:%d dir:%d -> w:%d h:%d rotation:%s vflip:%d\n",
+           inlink->w, inlink->h, trans->dir, outlink->w, outlink->h,
+           trans->dir == 0 || trans->dir == 1 ? "clockwise" : "counterclockwise",
+           trans->dir == 0 || trans->dir == 3);
+    return 0;
+}
+
+static void end_frame(AVFilterLink *inlink)
+{
+    TransContext *trans = inlink->dst->priv;
+    AVFilterBufferRef *inpic  = inlink->cur_buf;
+    AVFilterBufferRef *outpic = inlink->dst->outputs[0]->out_buf;
+    AVFilterLink *outlink = inlink->dst->outputs[0];
+    int plane;
+
+    for (plane = 0; outpic->data[plane]; plane++) {
+        int hsub = plane == 1 || plane == 2 ? trans->hsub : 0;
+        int vsub = plane == 1 || plane == 2 ? trans->vsub : 0;
+        int pixstep = trans->pixsteps[plane];
+        int inh  = inpic->video->h>>vsub;
+        int outw = outpic->video->w>>hsub;
+        int outh = outpic->video->h>>vsub;
+        uint8_t *out, *in;
+        int outlinesize, inlinesize;
+        int x, y;
+
+        out = outpic->data[plane]; outlinesize = outpic->linesize[plane];
+        in  = inpic ->data[plane]; inlinesize  = inpic ->linesize[plane];
+
+        if (trans->dir&1) {
+            in +=  inpic->linesize[plane] * (inh-1);
+            inlinesize *= -1;
+        }
+
+        if (trans->dir&2) {
+            out += outpic->linesize[plane] * (outh-1);
+            outlinesize *= -1;
+        }
+
+        for (y = 0; y < outh; y++) {
+            switch (pixstep) {
+            case 1:
+                for (x = 0; x < outw; x++)
+                    *(out + x) = *(in + x*inlinesize + y);
+                break;
+            case 2:
+                for (x = 0; x < outw; x++)
+                    *((uint16_t *)(out + 2*x)) = *((uint16_t *)(in + x*inlinesize + y*2));
+                break;
+            case 3:
+                for (x = 0; x < outw; x++) {
+                    int32_t v = AV_RB24(in + x*inlinesize + y*3);
+                    AV_WB24(out + 3*x, v);
+                }
+                break;
+            case 4:
+                for (x = 0; x < outw; x++)
+                    *((uint32_t *)(out + 4*x)) = *((uint32_t *)(in + x*inlinesize + y*4));
+                break;
+            }
+            out += outlinesize;
+        }
+    }
+
+    avfilter_unref_buffer(inpic);
+    avfilter_draw_slice(outlink, 0, outpic->video->h, 1);
+    avfilter_end_frame(outlink);
+    avfilter_unref_buffer(outpic);
+}
+
+static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *picref)
+{
+    AVFilterLink *outlink = inlink->dst->outputs[0];
+
+    outlink->out_buf = avfilter_get_video_buffer(outlink, AV_PERM_WRITE,
+                                                 outlink->w, outlink->h);
+    outlink->out_buf->pts = picref->pts;
+
+    if (picref->video->pixel_aspect.num == 0) {
+        outlink->out_buf->video->pixel_aspect = picref->video->pixel_aspect;
+    } else {
+        outlink->out_buf->video->pixel_aspect.num = picref->video->pixel_aspect.den;
+        outlink->out_buf->video->pixel_aspect.den = picref->video->pixel_aspect.num;
+    }
+
+    avfilter_start_frame(outlink, avfilter_ref_buffer(outlink->out_buf, ~0));
+}
+
+AVFilter avfilter_vf_transpose = {
+    .name      = "transpose",
+    .description = NULL_IF_CONFIG_SMALL("Transpose input video."),
+
+    .init = init,
+    .priv_size = sizeof(TransContext),
+
+    .query_formats = query_formats,
+
+    .inputs    = (AVFilterPad[]) {{ .name            = "default",
+                                    .type            = AVMEDIA_TYPE_VIDEO,
+                                    .start_frame     = start_frame,
+                                    .end_frame       = end_frame,
+                                    .min_perms       = AV_PERM_READ, },
+                                  { .name = NULL}},
+    .outputs   = (AVFilterPad[]) {{ .name            = "default",
+                                    .config_props    = config_props_output,
+                                    .type            = AVMEDIA_TYPE_VIDEO, },
+                                  { .name = NULL}},
+};
-- 
1.7.1


--envbJBWh7q8WU6mo--



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