[FFmpeg-devel] [PATCH] Setup for extracting quantization parameters from encoded streams

Juan De León juandl at google.com
Thu Jul 18 02:18:11 EEST 2019


---
 libavfilter/vf_extractqp.c      | 116 ++++++++++++++++++++++++++++++++
 libavutil/Makefile              |   2 +
 libavutil/quantization_params.c |  28 ++++++++
 libavutil/quantization_params.h |  98 +++++++++++++++++++++++++++
 4 files changed, 244 insertions(+)
 create mode 100644 libavfilter/vf_extractqp.c
 create mode 100644 libavutil/quantization_params.c
 create mode 100644 libavutil/quantization_params.h

diff --git a/libavfilter/vf_extractqp.c b/libavfilter/vf_extractqp.c
new file mode 100644
index 0000000000..4332012cc4
--- /dev/null
+++ b/libavfilter/vf_extractqp.c
@@ -0,0 +1,116 @@
+/*
+ * 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/frame.h"
+#include "libavutil/opt.h"
+#include "libavutil/quantization_params.h"
+#include "libavfilter/avfilter.h"
+#include "libavfilter/internal.h"
+
+typedef struct QPExtractContext {
+    const AVClass *class;
+    FILE *stats_file;
+    char *stats_file_str;
+} QPExtractContext;
+
+#define OFFSET(x) offsetof(QPExtractContext, x)
+#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
+
+static const AVOption qpextract_options[] = {
+    {"stats_file", "Set file to store QP information", OFFSET(stats_file_str), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, FLAGS },
+    {"f",          "Set file to store QP information", OFFSET(stats_file_str), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, FLAGS },
+    { NULL }
+};
+
+AVFILTER_DEFINE_CLASS(qpextract);
+
+static av_cold int init(AVFilterContext *ctx)
+{
+    QPExtractContext *s = ctx->priv;
+
+    if (s->stats_file_str) {
+        if (!strcmp(s->stats_file_str, "-")) {
+            s->stats_file = stdout;
+        } else {
+            s->stats_file = fopen(s->stats_file_str, "w");
+            if (!s->stats_file) {
+                int err = AVERROR(errno);
+                char buf[128];
+                av_strerror(err, buf, sizeof(buf));
+                av_log(ctx, AV_LOG_ERROR, "Could not open log file %s: %s\n",
+                       s->stats_file_str, buf);
+                return err;
+            }
+        }
+    }
+    return 0;
+}
+
+static av_cold int uninit(AVFilterContext *ctx) {
+    return 0;
+}
+
+static int filter_frame(AVFilterLink *inlink, AVFrame *in) {
+    AVFilterContext *ctx = inlink->dst;
+    AVFilterLink *outlink = ctx->outputs[0];
+    QPExtractContext *s = ctx->priv;
+    AVFrame *out = NULL;
+
+    if (ctx->is_disabled) {
+        return ff_filter_frame(outlink, in);
+    }
+
+    AVFrameSideData *sd = av_frame_get_side_data(in, AV_FRAME_DATA_QUANTIZATION_PARAMS);
+
+    if (!sd) {
+        fprintf(s->stats_file, "no side data");
+    }
+    else {
+        fprintf(s->stats_file, "yes side data");
+    }
+
+    return ff_filter_frame(outlink, in);
+}
+
+static const AVFilterPad qpextract_inputs[] = {
+    {
+        .name         = "default",
+        .type         = AVMEDIA_TYPE_VIDEO,
+        .filter_frame = filter_frame,
+    },
+    { NULL }
+};
+
+static const AVFilterPad qpextract_outputs[] = {
+    {
+        .name          = "default",
+        .type          = AVMEDIA_TYPE_VIDEO,
+    },
+    { NULL }
+};
+
+AVFilter ff_vf_qpextract = {
+    .name          = "extractqp",
+    .description   = NULL_IF_CONFIG_SMALL("Extract quantization parameters."),
+    .init          = init,
+    .uninit        = uninit,
+    .priv_size     = sizeof(QPExtractContext),
+    .priv_class    = &qpextract_class,
+    .inputs        = qpextract_inputs,
+    .outputs       = qpextract_outputs,
+};
diff --git a/libavutil/Makefile b/libavutil/Makefile
index 8a7a44e4b5..be1a9c3a9c 100644
--- a/libavutil/Makefile
+++ b/libavutil/Makefile
@@ -60,6 +60,7 @@ HEADERS = adler32.h                                                     \
           pixdesc.h                                                     \
           pixelutils.h                                                  \
           pixfmt.h                                                      \
+          quantization_params.h                                         \
           random_seed.h                                                 \
           rc4.h                                                         \
           rational.h                                                    \
@@ -140,6 +141,7 @@ OBJS = adler32.o                                                        \
        parseutils.o                                                     \
        pixdesc.o                                                        \
        pixelutils.o                                                     \
+       quantization_params.o                                            \
        random_seed.o                                                    \
        rational.o                                                       \
        reverse.o                                                        \
diff --git a/libavutil/quantization_params.c b/libavutil/quantization_params.c
new file mode 100644
index 0000000000..96ffd78dbb
--- /dev/null
+++ b/libavutil/quantization_params.c
@@ -0,0 +1,28 @@
+/*
+ * 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/quantization_params.h"
+
+/**
+ * Strings for names of enums, used by Filter
+ */
+const char* const QP_NAMES_H264[] = {"qp"};
+const char* const QP_NAMES_VP9[] = {"qydc", "qyac", "quvdc", "quvac", "qiydc", "qiyac",
+                              "qiuvdc", "qiuvac"};
+const char* const QP_NAMES_AV1[] = {"qydc", "qyac", "qudc", "quac", "qvdc", "qvac",
+                              "qiydc", "qiyac", "qiudc", "qiuac", "qivdc", "qivac"};
\ No newline at end of file
diff --git a/libavutil/quantization_params.h b/libavutil/quantization_params.h
new file mode 100644
index 0000000000..e986abe842
--- /dev/null
+++ b/libavutil/quantization_params.h
@@ -0,0 +1,98 @@
+/*
+ * 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
+ */
+
+#ifndef AVUTIL_QUANTIZATION_PARAMS_H
+#define AVUTIL_QUANTIZATION_PARAMS_H
+
+/**
+ * Data structure for extracting Quantization Parameters codec independent
+ */
+typedef struct AVQuantizationParams {
+    /**
+     * x and y coordinates of the block in pixels
+     */
+    int x, y;
+    /**
+     * width and height of the block in pixels
+     */
+    int w, h;
+    /**
+     * qp array, indexed by type according to
+     * the enum corresponding to the codec
+     * size depends on codec
+     */
+    int *type;
+} AVQuantizationParams;
+
+/**
+ * For storing an array of AVQuantization parameters and its size
+ * To be used as AVFrameSideData
+ */
+typedef struct AVQuantizationParamsArray {
+    /**
+     * AVQuantizationParams block array
+     */
+    AVQuantizationParams *qp_arr;
+    /**
+     * size of the array
+     */
+    int nb_blocks;
+} AVQuantizationParamsArray;
+
+/**
+ * Enums for different codecs to store qp in the type array
+ * Each enum must have an array of strings describing each field
+ * used for output
+ */
+extern const char* const QP_ENUM_NAMES_H264[];
+enum QP_ARR_INDEXES_FOR_H264 {
+        QP_H264 = 0,            // qp value
+        QP_TYPE_ARR_SIZE_H264   // used for allocating memory
+};
+
+extern const char* const QP_NAMES_VP9[];
+enum QP_ARR_INDEXES_FOR_VP9 {
+        QP_YDC_VP9 = 0,
+        QP_YAC_VP9,
+        QP_UVDC_VP9,
+        QP_UVAC_VP9,
+        QP_INDEX_YDC_VP9,
+        QP_INDEX_YAC_VP9,
+        QP_INDEX_UVDC_VP9,
+        QP_INDEX_UVAC_VP9,
+        QP_ARR_SIZE_VP9
+};
+
+extern const char* const QP_NAMES_AV1[];
+enum QP_ARR_INDEXES_FOR_AV1 {
+        QP_YDC_AV1 = 0,
+        QP_YAC_AV1,
+        QP_UDC_AV1,
+        QP_UAC_AV1,
+        QP_VDC_AV1,
+        QP_VAC_AV1,
+        QP_INDEX_YDC_AV1,
+        QP_INDEX_YAC_AV1,
+        QP_INDEX_UDC_AV1,
+        QP_INDEX_UAC_AV1,
+        QP_INDEX_VDC_AV1,
+        QP_INDEX_VAC_AV1,
+        QP_ARR_SIZE_AV1
+};
+
+#endif /* AVUTIL_QUANTIZATION_PARAMS_H */
-- 
2.22.0.510.g264f2c817a-goog



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