Merge commit '124e26971e69bb25f38c6c7cb3fa20c77cf10966'

* commit '124e26971e69bb25f38c6c7cb3fa20c77cf10966':
  lavfi: Hardware map filter

Merged-by: Clément Bœsch <cboesch@gopro.com>

4 files changed, 338 insertions, 2 deletions

diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 9c15ed62d2..d6daa7a8a8 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -198,6 +198,7 @@ OBJS-$(CONFIG_HQX_FILTER)                    += vf_hqx.o
 OBJS-$(CONFIG_HSTACK_FILTER)                 += vf_stack.o framesync.o
 OBJS-$(CONFIG_HUE_FILTER)                    += vf_hue.o
 OBJS-$(CONFIG_HWDOWNLOAD_FILTER)             += vf_hwdownload.o
+OBJS-$(CONFIG_HWMAP_FILTER)                  += vf_hwmap.o
 OBJS-$(CONFIG_HWUPLOAD_CUDA_FILTER)          += vf_hwupload_cuda.o
 OBJS-$(CONFIG_HWUPLOAD_FILTER)               += vf_hwupload.o
 OBJS-$(CONFIG_HYSTERESIS_FILTER)             += vf_hysteresis.o framesync.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 64b634e8f3..ec6ec048e8 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -209,6 +209,7 @@ static void register_all(void)
     REGISTER_FILTER(HSTACK,         hstack,         vf);
     REGISTER_FILTER(HUE,            hue,            vf);
     REGISTER_FILTER(HWDOWNLOAD,     hwdownload,     vf);
+    REGISTER_FILTER(HWMAP,          hwmap,          vf);
     REGISTER_FILTER(HWUPLOAD,       hwupload,       vf);
     REGISTER_FILTER(HWUPLOAD_CUDA,  hwupload_cuda,  vf);
     REGISTER_FILTER(HYSTERESIS,     hysteresis,     vf);
diff --git a/libavfilter/version.h b/libavfilter/version.h
index a798e911b0..784fa391bc 100644
--- a/libavfilter/version.h
+++ b/libavfilter/version.h
@@ -30,8 +30,8 @@
 #include "libavutil/version.h"
 
 #define LIBAVFILTER_VERSION_MAJOR   6
-#define LIBAVFILTER_VERSION_MINOR  78
-#define LIBAVFILTER_VERSION_MICRO 101
+#define LIBAVFILTER_VERSION_MINOR  79
+#define LIBAVFILTER_VERSION_MICRO 100
 
 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
                                                LIBAVFILTER_VERSION_MINOR, \
diff --git a/libavfilter/vf_hwmap.c b/libavfilter/vf_hwmap.c
new file mode 100644
index 0000000000..654477c6f2
--- /dev/null
+++ b/libavfilter/vf_hwmap.c
@@ -0,0 +1,334 @@
+/*
+ * 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 "libavutil/buffer.h"
+#include "libavutil/hwcontext.h"
+#include "libavutil/log.h"
+#include "libavutil/opt.h"
+#include "libavutil/pixdesc.h"
+
+#include "avfilter.h"
+#include "formats.h"
+#include "internal.h"
+#include "video.h"
+
+typedef struct HWMapContext {
+    const AVClass *class;
+
+    AVBufferRef   *hwdevice_ref;
+    AVBufferRef   *hwframes_ref;
+
+    int            mode;
+    int            map_backwards;
+} HWMapContext;
+
+static int hwmap_query_formats(AVFilterContext *avctx)
+{
+    int ret;
+
+    if ((ret = ff_formats_ref(ff_all_formats(AVMEDIA_TYPE_VIDEO),
+                              &avctx->inputs[0]->out_formats)) < 0 ||
+        (ret = ff_formats_ref(ff_all_formats(AVMEDIA_TYPE_VIDEO),
+                              &avctx->outputs[0]->in_formats)) < 0)
+        return ret;
+
+    return 0;
+}
+
+static int hwmap_config_output(AVFilterLink *outlink)
+{
+    AVFilterContext *avctx = outlink->src;
+    HWMapContext      *ctx = avctx->priv;
+    AVFilterLink   *inlink = avctx->inputs[0];
+    AVHWFramesContext *hwfc;
+    const AVPixFmtDescriptor *desc;
+    int err;
+
+    av_log(avctx, AV_LOG_DEBUG, "Configure hwmap %s -> %s.\n",
+           av_get_pix_fmt_name(inlink->format),
+           av_get_pix_fmt_name(outlink->format));
+
+    if (inlink->hw_frames_ctx) {
+        hwfc = (AVHWFramesContext*)inlink->hw_frames_ctx->data;
+
+        desc = av_pix_fmt_desc_get(outlink->format);
+        if (!desc)
+            return AVERROR(EINVAL);
+
+        if (inlink->format == hwfc->format &&
+            (desc->flags & AV_PIX_FMT_FLAG_HWACCEL)) {
+            // Map between two hardware formats (including the case of
+            // undoing an existing mapping).
+
+            ctx->hwdevice_ref = av_buffer_ref(avctx->hw_device_ctx);
+            if (!ctx->hwdevice_ref) {
+                err = AVERROR(ENOMEM);
+                goto fail;
+            }
+
+            err = av_hwframe_ctx_create_derived(&ctx->hwframes_ref,
+                                                outlink->format,
+                                                ctx->hwdevice_ref,
+                                                inlink->hw_frames_ctx, 0);
+            if (err < 0)
+                goto fail;
+
+        } else if ((outlink->format == hwfc->format &&
+                    inlink->format  == hwfc->sw_format) ||
+                   inlink->format == hwfc->format) {
+            // Map from a hardware format to a software format, or
+            // undo an existing such mapping.
+
+            ctx->hwdevice_ref = NULL;
+
+            ctx->hwframes_ref = av_buffer_ref(inlink->hw_frames_ctx);
+            if (!ctx->hwframes_ref) {
+                err = AVERROR(ENOMEM);
+                goto fail;
+            }
+
+        } else {
+            // Non-matching formats - not supported.
+
+            av_log(avctx, AV_LOG_ERROR, "Unsupported formats for "
+                   "hwmap: from %s (%s) to %s.\n",
+                   av_get_pix_fmt_name(inlink->format),
+                   av_get_pix_fmt_name(hwfc->format),
+                   av_get_pix_fmt_name(outlink->format));
+            err = AVERROR(EINVAL);
+            goto fail;
+        }
+    } else if (avctx->hw_device_ctx) {
+        // Map from a software format to a hardware format.  This
+        // creates a new hwframe context like hwupload, but then
+        // returns frames mapped from that to the previous link in
+        // order to fill them without an additional copy.
+
+        ctx->map_backwards = 1;
+
+        ctx->hwdevice_ref = av_buffer_ref(avctx->hw_device_ctx);
+        if (!ctx->hwdevice_ref) {
+            err = AVERROR(ENOMEM);
+            goto fail;
+        }
+
+        ctx->hwframes_ref = av_hwframe_ctx_alloc(ctx->hwdevice_ref);
+        if (!ctx->hwframes_ref) {
+            err = AVERROR(ENOMEM);
+            goto fail;
+        }
+        hwfc = (AVHWFramesContext*)ctx->hwframes_ref->data;
+
+        hwfc->format    = outlink->format;
+        hwfc->sw_format = inlink->format;
+        hwfc->width     = inlink->w;
+        hwfc->height    = inlink->h;
+
+        err = av_hwframe_ctx_init(ctx->hwframes_ref);
+        if (err < 0) {
+            av_log(avctx, AV_LOG_ERROR, "Failed to create frame "
+                   "context for backward mapping: %d.\n", err);
+            goto fail;
+        }
+
+    } else {
+        av_log(avctx, AV_LOG_ERROR, "Mapping requires a hardware "
+               "context (a device, or frames on input).\n");
+        return AVERROR(EINVAL);
+    }
+
+    outlink->hw_frames_ctx = av_buffer_ref(ctx->hwframes_ref);
+    if (!outlink->hw_frames_ctx) {
+        err = AVERROR(ENOMEM);
+        goto fail;
+    }
+
+    outlink->w = inlink->w;
+    outlink->h = inlink->h;
+
+    return 0;
+
+fail:
+    av_buffer_unref(&ctx->hwframes_ref);
+    av_buffer_unref(&ctx->hwdevice_ref);
+    return err;
+}
+
+static AVFrame *hwmap_get_buffer(AVFilterLink *inlink, int w, int h)
+{
+    AVFilterContext *avctx = inlink->dst;
+    AVFilterLink  *outlink = avctx->outputs[0];
+    HWMapContext      *ctx = avctx->priv;
+
+    if (ctx->map_backwards) {
+        AVFrame *src, *dst;
+        int err;
+
+        src = ff_get_video_buffer(outlink, w, h);
+        if (!src) {
+            av_log(avctx, AV_LOG_ERROR, "Failed to allocate source "
+                   "frame for software mapping.\n");
+            return NULL;
+        }
+
+        dst = av_frame_alloc();
+        if (!dst) {
+            av_frame_free(&src);
+            return NULL;
+        }
+
+        err = av_hwframe_map(dst, src, ctx->mode);
+        if (err) {
+            av_log(avctx, AV_LOG_ERROR, "Failed to map frame to "
+                   "software: %d.\n", err);
+            av_frame_free(&src);
+            av_frame_free(&dst);
+            return NULL;
+        }
+
+        av_frame_free(&src);
+        return dst;
+    } else {
+        return ff_default_get_video_buffer(inlink, w, h);
+    }
+}
+
+static int hwmap_filter_frame(AVFilterLink *link, AVFrame *input)
+{
+    AVFilterContext *avctx = link->dst;
+    AVFilterLink  *outlink = avctx->outputs[0];
+    HWMapContext      *ctx = avctx->priv;
+    AVFrame *map = NULL;
+    int err;
+
+    av_log(ctx, AV_LOG_DEBUG, "Filter input: %s, %ux%u (%"PRId64").\n",
+           av_get_pix_fmt_name(input->format),
+           input->width, input->height, input->pts);
+
+    map = av_frame_alloc();
+    if (!map) {
+        err = AVERROR(ENOMEM);
+        goto fail;
+    }
+
+    map->format = outlink->format;
+    map->hw_frames_ctx = av_buffer_ref(ctx->hwframes_ref);
+    if (!map->hw_frames_ctx) {
+        err = AVERROR(ENOMEM);
+        goto fail;
+    }
+
+    if (ctx->map_backwards && !input->hw_frames_ctx) {
+        // If we mapped backwards from hardware to software, we need
+        // to attach the hardware frame context to the input frame to
+        // make the mapping visible to av_hwframe_map().
+        input->hw_frames_ctx = av_buffer_ref(ctx->hwframes_ref);
+        if (!input->hw_frames_ctx) {
+            err = AVERROR(ENOMEM);
+            goto fail;
+        }
+    }
+
+    err = av_hwframe_map(map, input, ctx->mode);
+    if (err < 0) {
+        av_log(avctx, AV_LOG_ERROR, "Failed to map frame: %d.\n", err);
+        goto fail;
+    }
+
+    err = av_frame_copy_props(map, input);
+    if (err < 0)
+        goto fail;
+
+    av_frame_free(&input);
+
+    av_log(ctx, AV_LOG_DEBUG, "Filter output: %s, %ux%u (%"PRId64").\n",
+           av_get_pix_fmt_name(map->format),
+           map->width, map->height, map->pts);
+
+    return ff_filter_frame(outlink, map);
+
+fail:
+    av_frame_free(&input);
+    av_frame_free(&map);
+    return err;
+}
+
+static av_cold void hwmap_uninit(AVFilterContext *avctx)
+{
+    HWMapContext *ctx = avctx->priv;
+
+    av_buffer_unref(&ctx->hwframes_ref);
+    av_buffer_unref(&ctx->hwdevice_ref);
+}
+
+#define OFFSET(x) offsetof(HWMapContext, x)
+#define FLAGS (AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM)
+static const AVOption hwmap_options[] = {
+    { "mode", "Frame mapping mode",
+      OFFSET(mode), AV_OPT_TYPE_FLAGS,
+      { .i64 = AV_HWFRAME_MAP_READ | AV_HWFRAME_MAP_WRITE },
+      0, INT_MAX, FLAGS, "mode" },
+
+    { "read", "Mapping should be readable",
+      0, AV_OPT_TYPE_CONST, { .i64 = AV_HWFRAME_MAP_READ },
+      INT_MIN, INT_MAX, FLAGS, "mode" },
+    { "write", "Mapping should be writeable",
+      0, AV_OPT_TYPE_CONST, { .i64 = AV_HWFRAME_MAP_WRITE },
+      INT_MIN, INT_MAX, FLAGS, "mode" },
+    { "overwrite", "Mapping will always overwrite the entire frame",
+      0, AV_OPT_TYPE_CONST, { .i64 = AV_HWFRAME_MAP_OVERWRITE },
+      INT_MIN, INT_MAX, FLAGS, "mode" },
+    { "direct", "Mapping should not involve any copying",
+      0, AV_OPT_TYPE_CONST, { .i64 = AV_HWFRAME_MAP_DIRECT },
+      INT_MIN, INT_MAX, FLAGS, "mode" },
+
+    { NULL }
+};
+
+AVFILTER_DEFINE_CLASS(hwmap);
+
+static const AVFilterPad hwmap_inputs[] = {
+    {
+        .name             = "default",
+        .type             = AVMEDIA_TYPE_VIDEO,
+        .get_video_buffer = hwmap_get_buffer,
+        .filter_frame     = hwmap_filter_frame,
+    },
+    { NULL }
+};
+
+static const AVFilterPad hwmap_outputs[] = {
+    {
+        .name         = "default",
+        .type         = AVMEDIA_TYPE_VIDEO,
+        .config_props = hwmap_config_output,
+    },
+    { NULL }
+};
+
+AVFilter ff_vf_hwmap = {
+    .name           = "hwmap",
+    .description    = NULL_IF_CONFIG_SMALL("Map hardware frames"),
+    .uninit         = hwmap_uninit,
+    .priv_size      = sizeof(HWMapContext),
+    .priv_class     = &hwmap_class,
+    .query_formats  = hwmap_query_formats,
+    .inputs         = hwmap_inputs,
+    .outputs        = hwmap_outputs,
+    .flags_internal = FF_FILTER_FLAG_HWFRAME_AWARE,
+};