ffmpeg: Support setting the hardware device to use when filtering

This only supports one device globally, but more can be used by
passing them with input streams in hw_frames_ctx or by deriving new
devices inside a filter graph with hwmap.

(cherry picked from commit e669db76108de8d7a36c2274c99da82cc94d1dd1)

1 files changed, 17 insertions, 0 deletions

diff --git a/ffmpeg_opt.c b/ffmpeg_opt.c
index be9c6fb6ac..bb6001f534 100644
--- a/ffmpeg_opt.c
+++ b/ffmpeg_opt.c
@@ -98,6 +98,7 @@ const HWAccel hwaccels[] = {
 };
 int hwaccel_lax_profile_check = 0;
 AVBufferRef *hw_device_ctx;
+HWDevice *filter_hw_device;
 
 char *vstats_filename;
 char *sdp_filename;
@@ -495,6 +496,20 @@ static int opt_init_hw_device(void *optctx, const char *opt, const char *arg)
     }
 }
 
+static int opt_filter_hw_device(void *optctx, const char *opt, const char *arg)
+{
+    if (filter_hw_device) {
+        av_log(NULL, AV_LOG_ERROR, "Only one filter device can be used.\n");
+        return AVERROR(EINVAL);
+    }
+    filter_hw_device = hw_device_get_by_name(arg);
+    if (!filter_hw_device) {
+        av_log(NULL, AV_LOG_ERROR, "Invalid filter device %s.\n", arg);
+        return AVERROR(EINVAL);
+    }
+    return 0;
+}
+
 /**
  * Parse a metadata specifier passed as 'arg' parameter.
  * @param arg  metadata string to parse
@@ -3708,6 +3723,8 @@ const OptionDef options[] = {
 
     { "init_hw_device", HAS_ARG | OPT_EXPERT, { .func_arg = opt_init_hw_device },
         "initialise hardware device", "args" },
+    { "filter_hw_device", HAS_ARG | OPT_EXPERT, { .func_arg = opt_filter_hw_device },
+        "set hardware device used when filtering", "device" },
 
     { NULL, },
 };