[FFmpeg-cvslog] vaapi_encode: Clean up rate control configuration

Mark Thompson git at videolan.org
Sun Sep 23 18:47:22 EEST 2018


ffmpeg | branch: master | Mark Thompson <sw at jkqxz.net> | Tue Sep 18 23:30:45 2018 +0100| [af532c921575eb8ee805cc2c64a914f6302442e1] | committer: Mark Thompson

vaapi_encode: Clean up rate control configuration

Query which modes are supported and select between VBR and CBR based
on that - this removes all of the codec-specific rate control mode
selection code.

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=af532c921575eb8ee805cc2c64a914f6302442e1
---

 doc/encoders.texi               |   2 -
 libavcodec/vaapi_encode.c       | 181 +++++++++++++++++++++++++++++-----------
 libavcodec/vaapi_encode.h       |   6 +-
 libavcodec/vaapi_encode_h264.c  |  18 +---
 libavcodec/vaapi_encode_h265.c  |  14 +---
 libavcodec/vaapi_encode_mjpeg.c |   3 +-
 libavcodec/vaapi_encode_mpeg2.c |   9 +-
 libavcodec/vaapi_encode_vp8.c   |  13 +--
 libavcodec/vaapi_encode_vp9.c   |  13 +--
 9 files changed, 145 insertions(+), 114 deletions(-)

diff --git a/doc/encoders.texi b/doc/encoders.texi
index 9bf0b04028..e550bd9893 100644
--- a/doc/encoders.texi
+++ b/doc/encoders.texi
@@ -2643,8 +2643,6 @@ Always encodes using the standard quantisation and huffman tables -
 @item mpeg2_vaapi
 @option{profile} and @option{level} set the value of @emph{profile_and_level_indication}.
 
-No rate control is supported.
-
 @item vp8_vaapi
 B-frames are not supported.
 
diff --git a/libavcodec/vaapi_encode.c b/libavcodec/vaapi_encode.c
index 1969c9252f..25d89c65c9 100644
--- a/libavcodec/vaapi_encode.c
+++ b/libavcodec/vaapi_encode.c
@@ -1213,7 +1213,6 @@ static av_cold int vaapi_encode_config_attributes(AVCodecContext *avctx)
     int i;
 
     VAConfigAttrib attr[] = {
-        { VAConfigAttribRateControl      },
         { VAConfigAttribEncMaxRefFrames  },
         { VAConfigAttribEncPackedHeaders },
     };
@@ -1237,32 +1236,6 @@ static av_cold int vaapi_encode_config_attributes(AVCodecContext *avctx)
             continue;
         }
         switch (attr[i].type) {
-        case VAConfigAttribRateControl:
-            // Hack for backward compatibility: CBR was the only
-            // usable RC mode for a long time, so old drivers will
-            // only have it.  Normal default options may now choose
-            // VBR and then fail, however, so override it here with
-            // CBR if that is the only supported mode.
-            if (ctx->va_rc_mode == VA_RC_VBR &&
-                !(attr[i].value & VA_RC_VBR) &&
-                (attr[i].value & VA_RC_CBR)) {
-                av_log(avctx, AV_LOG_WARNING, "VBR rate control is "
-                       "not supported with this driver version; "
-                       "using CBR instead.\n");
-                ctx->va_rc_mode = VA_RC_CBR;
-            }
-            if (!(ctx->va_rc_mode & attr[i].value)) {
-                av_log(avctx, AV_LOG_ERROR, "Rate control mode %#x "
-                       "is not supported (mask: %#x).\n",
-                       ctx->va_rc_mode, attr[i].value);
-                return AVERROR(EINVAL);
-            }
-            ctx->config_attributes[ctx->nb_config_attributes++] =
-                (VAConfigAttrib) {
-                .type  = VAConfigAttribRateControl,
-                .value = ctx->va_rc_mode,
-            };
-            break;
         case VAConfigAttribEncMaxRefFrames:
         {
             unsigned int ref_l0 = attr[i].value & 0xffff;
@@ -1309,44 +1282,152 @@ static av_cold int vaapi_encode_config_attributes(AVCodecContext *avctx)
 static av_cold int vaapi_encode_init_rate_control(AVCodecContext *avctx)
 {
     VAAPIEncodeContext *ctx = avctx->priv_data;
-    int rc_bits_per_second;
-    int rc_target_percentage;
-    int rc_window_size;
-    int hrd_buffer_size;
-    int hrd_initial_buffer_fullness;
+    int64_t rc_bits_per_second;
+    int     rc_target_percentage;
+    int     rc_window_size;
+    int64_t hrd_buffer_size;
+    int64_t hrd_initial_buffer_fullness;
     int fr_num, fr_den;
+    VAConfigAttrib rc_attr = { VAConfigAttribRateControl };
+    VAStatus vas;
+
+    vas = vaGetConfigAttributes(ctx->hwctx->display,
+                                ctx->va_profile, ctx->va_entrypoint,
+                                &rc_attr, 1);
+    if (vas != VA_STATUS_SUCCESS) {
+        av_log(avctx, AV_LOG_ERROR, "Failed to query rate control "
+               "config attribute: %d (%s).\n", vas, vaErrorStr(vas));
+        return AVERROR_EXTERNAL;
+    }
+
+    if (rc_attr.value == VA_ATTRIB_NOT_SUPPORTED) {
+        av_log(avctx, AV_LOG_VERBOSE, "Driver does not report any "
+               "supported rate control modes: assuming constant-quality.\n");
+        ctx->va_rc_mode = VA_RC_CQP;
+        return 0;
+    }
+    if (avctx->flags & AV_CODEC_FLAG_QSCALE ||
+        avctx->bit_rate <= 0) {
+        if (rc_attr.value & VA_RC_CQP) {
+            av_log(avctx, AV_LOG_VERBOSE, "Using constant-quality mode.\n");
+            ctx->va_rc_mode = VA_RC_CQP;
+            if (avctx->bit_rate > 0 || avctx->rc_max_rate > 0) {
+                av_log(avctx, AV_LOG_WARNING, "Bitrate target parameters "
+                       "ignored in constant-quality mode.\n");
+            }
+            return 0;
+        } else {
+            av_log(avctx, AV_LOG_ERROR, "Driver does not support "
+                   "constant-quality mode (%#x).\n", rc_attr.value);
+            return AVERROR(EINVAL);
+        }
+    }
 
-    if (avctx->bit_rate > INT32_MAX) {
-        av_log(avctx, AV_LOG_ERROR, "Target bitrate of 2^31 bps or "
-               "higher is not supported.\n");
+    if (!(rc_attr.value & (VA_RC_CBR | VA_RC_VBR))) {
+        av_log(avctx, AV_LOG_ERROR, "Driver does not support any "
+               "bitrate-targetted rate control modes.\n");
         return AVERROR(EINVAL);
     }
 
     if (avctx->rc_buffer_size)
         hrd_buffer_size = avctx->rc_buffer_size;
+    else if (avctx->rc_max_rate > 0)
+        hrd_buffer_size = avctx->rc_max_rate;
     else
         hrd_buffer_size = avctx->bit_rate;
-    if (avctx->rc_initial_buffer_occupancy)
+    if (avctx->rc_initial_buffer_occupancy) {
+        if (avctx->rc_initial_buffer_occupancy > hrd_buffer_size) {
+            av_log(avctx, AV_LOG_ERROR, "Invalid RC buffer settings: "
+                   "must have initial buffer size (%d) < "
+                   "buffer size (%"PRId64").\n",
+                   avctx->rc_initial_buffer_occupancy, hrd_buffer_size);
+            return AVERROR(EINVAL);
+        }
         hrd_initial_buffer_fullness = avctx->rc_initial_buffer_occupancy;
-    else
+    } else {
         hrd_initial_buffer_fullness = hrd_buffer_size * 3 / 4;
+    }
+
+    if (avctx->rc_max_rate && avctx->rc_max_rate < avctx->bit_rate) {
+        av_log(avctx, AV_LOG_ERROR, "Invalid bitrate settings: must have "
+               "bitrate (%"PRId64") <= maxrate (%"PRId64").\n",
+               avctx->bit_rate, avctx->rc_max_rate);
+        return AVERROR(EINVAL);
+    }
+
+    if (avctx->rc_max_rate > avctx->bit_rate) {
+        if (!(rc_attr.value & VA_RC_VBR)) {
+            av_log(avctx, AV_LOG_WARNING, "Driver does not support "
+                   "VBR mode (%#x), using CBR mode instead.\n",
+                   rc_attr.value);
+            ctx->va_rc_mode = VA_RC_CBR;
+
+            rc_bits_per_second   = avctx->bit_rate;
+            rc_target_percentage = 100;
+        } else {
+            ctx->va_rc_mode = VA_RC_VBR;
+
+            rc_bits_per_second   = avctx->rc_max_rate;
+            rc_target_percentage = (avctx->bit_rate * 100) /
+                                   avctx->rc_max_rate;
+        }
+
+    } else if (avctx->rc_max_rate == avctx->bit_rate) {
+        if (!(rc_attr.value & VA_RC_CBR)) {
+            av_log(avctx, AV_LOG_WARNING, "Driver does not support "
+                   "CBR mode (%#x), using VBR mode instead.\n",
+                   rc_attr.value);
+            ctx->va_rc_mode = VA_RC_VBR;
+        } else {
+            ctx->va_rc_mode = VA_RC_CBR;
+        }
 
-    if (ctx->va_rc_mode == VA_RC_CBR) {
         rc_bits_per_second   = avctx->bit_rate;
         rc_target_percentage = 100;
-        rc_window_size       = 1000;
+
     } else {
-        if (avctx->rc_max_rate < avctx->bit_rate) {
-            // Max rate is unset or invalid, just use the normal bitrate.
+        if (rc_attr.value & VA_RC_VBR) {
+            ctx->va_rc_mode = VA_RC_VBR;
+
+            // We only have a target bitrate, but VAAPI requires that a
+            // maximum rate be supplied as well.  Since the user has
+            // offered no particular constraint, arbitrarily pick a
+            // maximum rate of double the target rate.
+            rc_bits_per_second   = 2 * avctx->bit_rate;
+            rc_target_percentage = 50;
+        } else {
+            ctx->va_rc_mode = VA_RC_CBR;
+
             rc_bits_per_second   = avctx->bit_rate;
             rc_target_percentage = 100;
-        } else {
-            rc_bits_per_second   = avctx->rc_max_rate;
-            rc_target_percentage = (avctx->bit_rate * 100) / rc_bits_per_second;
         }
-        rc_window_size = (hrd_buffer_size * 1000) / avctx->bit_rate;
     }
 
+    rc_window_size = (hrd_buffer_size * 1000) / rc_bits_per_second;
+
+    av_log(avctx, AV_LOG_VERBOSE, "RC mode: %s, %d%% of %"PRId64" bps "
+           "over %d ms.\n", ctx->va_rc_mode == VA_RC_VBR ? "VBR" : "CBR",
+           rc_target_percentage, rc_bits_per_second, rc_window_size);
+    av_log(avctx, AV_LOG_VERBOSE, "RC buffer: %"PRId64" bits, "
+           "initial fullness %"PRId64" bits.\n",
+           hrd_buffer_size, hrd_initial_buffer_fullness);
+
+    if (rc_bits_per_second          > UINT32_MAX ||
+        hrd_buffer_size             > UINT32_MAX ||
+        hrd_initial_buffer_fullness > UINT32_MAX) {
+        av_log(avctx, AV_LOG_ERROR, "RC parameters of 2^32 or "
+               "greater are not supported by VAAPI.\n");
+        return AVERROR(EINVAL);
+    }
+
+    ctx->va_bit_rate = rc_bits_per_second;
+
+    ctx->config_attributes[ctx->nb_config_attributes++] =
+        (VAConfigAttrib) {
+        .type  = VAConfigAttribRateControl,
+        .value = ctx->va_rc_mode,
+    };
+
     ctx->rc_params.misc.type = VAEncMiscParameterTypeRateControl;
     ctx->rc_params.rc = (VAEncMiscParameterRateControl) {
         .bits_per_second   = rc_bits_per_second,
@@ -1607,6 +1688,10 @@ av_cold int ff_vaapi_encode_init(AVCodecContext *avctx)
     if (err < 0)
         goto fail;
 
+    err = vaapi_encode_init_rate_control(avctx);
+    if (err < 0)
+        goto fail;
+
     err = vaapi_encode_config_attributes(avctx);
     if (err < 0)
         goto fail;
@@ -1654,12 +1739,6 @@ av_cold int ff_vaapi_encode_init(AVCodecContext *avctx)
         goto fail;
     }
 
-    if (ctx->va_rc_mode & ~VA_RC_CQP) {
-        err = vaapi_encode_init_rate_control(avctx);
-        if (err < 0)
-            goto fail;
-    }
-
     if (ctx->codec->configure) {
         err = ctx->codec->configure(avctx);
         if (err < 0)
diff --git a/libavcodec/vaapi_encode.h b/libavcodec/vaapi_encode.h
index 30c3f7fbec..e61e900e8d 100644
--- a/libavcodec/vaapi_encode.h
+++ b/libavcodec/vaapi_encode.h
@@ -116,8 +116,6 @@ typedef struct VAAPIEncodeContext {
     // Use low power encoding mode.
     int             low_power;
 
-    // Rate control mode.
-    unsigned int    va_rc_mode;
     // Supported packed headers (initially the desired set, modified
     // later to what is actually supported).
     unsigned int    va_packed_headers;
@@ -138,6 +136,10 @@ typedef struct VAAPIEncodeContext {
     VAProfile       va_profile;
     // Encoding entrypoint (VAEntryoint*).
     VAEntrypoint    va_entrypoint;
+    // Rate control mode.
+    unsigned int    va_rc_mode;
+    // Bitrate for codec-specific encoder parameters.
+    unsigned int    va_bit_rate;
 
     // Configuration attributes to use when creating va_config.
     VAConfigAttrib  config_attributes[MAX_CONFIG_ATTRIBUTES];
diff --git a/libavcodec/vaapi_encode_h264.c b/libavcodec/vaapi_encode_h264.c
index 69e95dd340..c63766d918 100644
--- a/libavcodec/vaapi_encode_h264.c
+++ b/libavcodec/vaapi_encode_h264.c
@@ -425,9 +425,9 @@ static int vaapi_encode_h264_init_sequence_params(AVCodecContext *avctx)
         // Try to scale these to a sensible range so that the
         // golomb encode of the value is not overlong.
         hrd->bit_rate_scale =
-            av_clip_uintp2(av_log2(avctx->bit_rate) - 15 - 6, 4);
+            av_clip_uintp2(av_log2(ctx->va_bit_rate) - 15 - 6, 4);
         hrd->bit_rate_value_minus1[0] =
-            (avctx->bit_rate >> hrd->bit_rate_scale + 6) - 1;
+            (ctx->va_bit_rate >> hrd->bit_rate_scale + 6) - 1;
 
         hrd->cpb_size_scale =
             av_clip_uintp2(av_log2(ctx->hrd_params.hrd.buffer_size) - 15 - 4, 4);
@@ -497,7 +497,7 @@ static int vaapi_encode_h264_init_sequence_params(AVCodecContext *avctx)
         .intra_idr_period = avctx->gop_size,
         .ip_period        = ctx->b_per_p + 1,
 
-        .bits_per_second       = avctx->bit_rate,
+        .bits_per_second       = ctx->va_bit_rate,
         .max_num_ref_frames    = sps->max_num_ref_frames,
         .picture_width_in_mbs  = sps->pic_width_in_mbs_minus1 + 1,
         .picture_height_in_mbs = sps->pic_height_in_map_units_minus1 + 1,
@@ -823,10 +823,6 @@ static av_cold int vaapi_encode_h264_configure(AVCodecContext *avctx)
         priv->fixed_qp_p   = 26;
         priv->fixed_qp_b   = 26;
 
-        av_log(avctx, AV_LOG_DEBUG, "Using %s-bitrate = %"PRId64" bps.\n",
-               ctx->va_rc_mode == VA_RC_CBR ? "constant" : "variable",
-               avctx->bit_rate);
-
     } else {
         av_assert0(0 && "Invalid RC mode.");
     }
@@ -934,14 +930,6 @@ static av_cold int vaapi_encode_h264_init(AVCodecContext *avctx)
         return AVERROR_PATCHWELCOME;
     }
 
-    if (avctx->bit_rate > 0) {
-        if (avctx->rc_max_rate == avctx->bit_rate)
-            ctx->va_rc_mode = VA_RC_CBR;
-        else
-            ctx->va_rc_mode = VA_RC_VBR;
-    } else
-        ctx->va_rc_mode = VA_RC_CQP;
-
     ctx->va_packed_headers =
         VA_ENC_PACKED_HEADER_SEQUENCE | // SPS and PPS.
         VA_ENC_PACKED_HEADER_SLICE    | // Slice headers.
diff --git a/libavcodec/vaapi_encode_h265.c b/libavcodec/vaapi_encode_h265.c
index b8b66b87cb..b296919b37 100644
--- a/libavcodec/vaapi_encode_h265.c
+++ b/libavcodec/vaapi_encode_h265.c
@@ -512,7 +512,7 @@ static int vaapi_encode_h265_init_sequence_params(AVCodecContext *avctx)
         .intra_period     = avctx->gop_size,
         .intra_idr_period = avctx->gop_size,
         .ip_period        = ctx->b_per_p + 1,
-        .bits_per_second   = avctx->bit_rate,
+        .bits_per_second  = ctx->va_bit_rate,
 
         .pic_width_in_luma_samples  = sps->pic_width_in_luma_samples,
         .pic_height_in_luma_samples = sps->pic_height_in_luma_samples,
@@ -1014,10 +1014,6 @@ static av_cold int vaapi_encode_h265_configure(AVCodecContext *avctx)
         priv->fixed_qp_p   = 30;
         priv->fixed_qp_b   = 30;
 
-        av_log(avctx, AV_LOG_DEBUG, "Using %s-bitrate = %"PRId64" bps.\n",
-               ctx->va_rc_mode == VA_RC_CBR ? "constant" : "variable",
-               avctx->bit_rate);
-
     } else {
         av_assert0(0 && "Invalid RC mode.");
     }
@@ -1068,14 +1064,6 @@ static av_cold int vaapi_encode_h265_init(AVCodecContext *avctx)
     if (avctx->level == FF_LEVEL_UNKNOWN)
         avctx->level = priv->level;
 
-    if (avctx->bit_rate > 0) {
-        if (avctx->rc_max_rate == avctx->bit_rate)
-            ctx->va_rc_mode = VA_RC_CBR;
-        else
-            ctx->va_rc_mode = VA_RC_VBR;
-    } else
-        ctx->va_rc_mode = VA_RC_CQP;
-
     ctx->va_packed_headers =
         VA_ENC_PACKED_HEADER_SEQUENCE | // VPS, SPS and PPS.
         VA_ENC_PACKED_HEADER_SLICE    | // Slice headers.
diff --git a/libavcodec/vaapi_encode_mjpeg.c b/libavcodec/vaapi_encode_mjpeg.c
index b328beaa09..67ac2fba96 100644
--- a/libavcodec/vaapi_encode_mjpeg.c
+++ b/libavcodec/vaapi_encode_mjpeg.c
@@ -388,8 +388,6 @@ static av_cold int vaapi_encode_mjpeg_init(AVCodecContext *avctx)
 
     ctx->codec = &vaapi_encode_type_mjpeg;
 
-    ctx->va_rc_mode = VA_RC_CQP;
-
     // The JPEG image header - see note above.
     ctx->va_packed_headers =
         VA_ENC_PACKED_HEADER_RAW_DATA;
@@ -402,6 +400,7 @@ static av_cold int vaapi_encode_mjpeg_init(AVCodecContext *avctx)
 
 static const AVCodecDefault vaapi_encode_mjpeg_defaults[] = {
     { "global_quality", "80" },
+    { "b",              "0"  },
     { NULL },
 };
 
diff --git a/libavcodec/vaapi_encode_mpeg2.c b/libavcodec/vaapi_encode_mpeg2.c
index db79d72115..ff86b8817e 100644
--- a/libavcodec/vaapi_encode_mpeg2.c
+++ b/libavcodec/vaapi_encode_mpeg2.c
@@ -188,8 +188,8 @@ static int vaapi_encode_mpeg2_init_sequence_params(AVCodecContext *avctx)
     memset(pce,  0, sizeof(*pce));
 
 
-    if (avctx->bit_rate > 0) {
-        priv->bit_rate = (avctx->bit_rate + 399) / 400;
+    if (ctx->va_bit_rate > 0) {
+        priv->bit_rate = (ctx->va_bit_rate + 399) / 400;
     } else {
         // Unknown (not a bitrate-targetting mode), so just use the
         // highest value.
@@ -361,7 +361,7 @@ static int vaapi_encode_mpeg2_init_sequence_params(AVCodecContext *avctx)
         .picture_width  = avctx->width,
         .picture_height = avctx->height,
 
-        .bits_per_second          = avctx->bit_rate,
+        .bits_per_second          = ctx->va_bit_rate,
         .frame_rate               = av_q2d(priv->frame_rate),
         .aspect_ratio_information = sh->aspect_ratio_information,
         .vbv_buffer_size          = priv->vbv_buffer_size,
@@ -615,8 +615,6 @@ static av_cold int vaapi_encode_mpeg2_init(AVCodecContext *avctx)
         return AVERROR(EINVAL);
     }
 
-    ctx->va_rc_mode    = VA_RC_CQP;
-
     ctx->va_packed_headers = VA_ENC_PACKED_HEADER_SEQUENCE |
                              VA_ENC_PACKED_HEADER_PICTURE;
 
@@ -666,6 +664,7 @@ static const AVOption vaapi_encode_mpeg2_options[] = {
 };
 
 static const AVCodecDefault vaapi_encode_mpeg2_defaults[] = {
+    { "b",              "0"   },
     { "bf",             "1"   },
     { "g",              "120" },
     { "i_qfactor",      "1"   },
diff --git a/libavcodec/vaapi_encode_vp8.c b/libavcodec/vaapi_encode_vp8.c
index 9588826bfb..40871a6bbf 100644
--- a/libavcodec/vaapi_encode_vp8.c
+++ b/libavcodec/vaapi_encode_vp8.c
@@ -65,7 +65,7 @@ static int vaapi_encode_vp8_init_sequence_params(AVCodecContext *avctx)
     vseq->kf_auto = 0;
 
     if (!(ctx->va_rc_mode & VA_RC_CQP)) {
-        vseq->bits_per_second = avctx->bit_rate;
+        vseq->bits_per_second = ctx->va_bit_rate;
         vseq->intra_period    = avctx->gop_size;
     }
 
@@ -205,17 +205,6 @@ static av_cold int vaapi_encode_vp8_init(AVCodecContext *avctx)
 
     ctx->codec = &vaapi_encode_type_vp8;
 
-    if (avctx->flags & AV_CODEC_FLAG_QSCALE) {
-        ctx->va_rc_mode = VA_RC_CQP;
-    } else if (avctx->bit_rate > 0) {
-        if (avctx->rc_max_rate == avctx->bit_rate)
-            ctx->va_rc_mode = VA_RC_CBR;
-        else
-            ctx->va_rc_mode = VA_RC_VBR;
-    } else {
-        ctx->va_rc_mode = VA_RC_CQP;
-    }
-
     // Packed headers are not currently supported.
     ctx->va_packed_headers = 0;
 
diff --git a/libavcodec/vaapi_encode_vp9.c b/libavcodec/vaapi_encode_vp9.c
index 4d7cec0520..e400bc8b79 100644
--- a/libavcodec/vaapi_encode_vp9.c
+++ b/libavcodec/vaapi_encode_vp9.c
@@ -71,7 +71,7 @@ static int vaapi_encode_vp9_init_sequence_params(AVCodecContext *avctx)
     vseq->kf_auto = 0;
 
     if (!(ctx->va_rc_mode & VA_RC_CQP)) {
-        vseq->bits_per_second = avctx->bit_rate;
+        vseq->bits_per_second = ctx->va_bit_rate;
         vseq->intra_period    = avctx->gop_size;
     }
 
@@ -227,17 +227,6 @@ static av_cold int vaapi_encode_vp9_init(AVCodecContext *avctx)
 
     ctx->codec = &vaapi_encode_type_vp9;
 
-    if (avctx->flags & AV_CODEC_FLAG_QSCALE) {
-        ctx->va_rc_mode = VA_RC_CQP;
-    } else if (avctx->bit_rate > 0) {
-        if (avctx->bit_rate == avctx->rc_max_rate)
-            ctx->va_rc_mode = VA_RC_CBR;
-        else
-            ctx->va_rc_mode = VA_RC_VBR;
-    } else {
-        ctx->va_rc_mode = VA_RC_CQP;
-    }
-
     // Packed headers are not currently supported.
     ctx->va_packed_headers = 0;
 



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