From fcd9051a9167f48083f0edc4bf44b3d09e568091 Mon Sep 17 00:00:00 2001 From: Elias Carotti Date: Mon, 10 Jul 2023 14:34:53 +0200 Subject: [PATCH] Add side data type to provide hint to the video encoders about unchanged portions of each frame. Signed-off-by: Anton Khirnov --- doc/APIchanges | 3 ++ libavutil/Makefile | 2 + libavutil/frame.h | 10 ++++ libavutil/version.h | 2 +- libavutil/video_hint.c | 82 ++++++++++++++++++++++++++++++++ libavutil/video_hint.h | 105 +++++++++++++++++++++++++++++++++++++++++ 6 files changed, 203 insertions(+), 1 deletion(-) create mode 100644 libavutil/video_hint.c create mode 100644 libavutil/video_hint.h diff --git a/doc/APIchanges b/doc/APIchanges index 5afe8bcb75..2adc7b5225 100644 --- a/doc/APIchanges +++ b/doc/APIchanges @@ -2,6 +2,9 @@ The last version increases of all libraries were on 2023-02-09 API changes, most recent first: +2023-07-xx - xxxxxxxxxx - lavu 58.15.100 - video_hint.h + Add AVVideoHint API. + 2023-07-xx - xxxxxxxxxx - lavc 60 - avcodec.h Deprecate AV_CODEC_FLAG_DROPCHANGED without replacement. diff --git a/libavutil/Makefile b/libavutil/Makefile index bd9c6f9e32..7828c94dc5 100644 --- a/libavutil/Makefile +++ b/libavutil/Makefile @@ -91,6 +91,7 @@ HEADERS = adler32.h \ tea.h \ tx.h \ film_grain_params.h \ + video_hint.h ARCH_HEADERS = bswap.h \ intmath.h \ @@ -181,6 +182,7 @@ OBJS = adler32.o \ uuid.o \ version.o \ video_enc_params.o \ + video_hint.o \ film_grain_params.o \ diff --git a/libavutil/frame.h b/libavutil/frame.h index a491315f25..c0c1b23db7 100644 --- a/libavutil/frame.h +++ b/libavutil/frame.h @@ -214,6 +214,16 @@ enum AVFrameSideDataType { * Ambient viewing environment metadata, as defined by H.274. */ AV_FRAME_DATA_AMBIENT_VIEWING_ENVIRONMENT, + + /** + * Provide encoder-specific hinting information about changed/unchanged + * portions of a frame. It can be used to pass information about which + * macroblocks can be skipped because they didn't change from the + * corresponding ones in the previous frame. This could be useful for + * applications which know this information in advance to speed up + * encoding. + */ + AV_FRAME_DATA_VIDEO_HINT, }; enum AVActiveFormatDescription { diff --git a/libavutil/version.h b/libavutil/version.h index 24af520e08..9e798b0e3f 100644 --- a/libavutil/version.h +++ b/libavutil/version.h @@ -79,7 +79,7 @@ */ #define LIBAVUTIL_VERSION_MAJOR 58 -#define LIBAVUTIL_VERSION_MINOR 14 +#define LIBAVUTIL_VERSION_MINOR 15 #define LIBAVUTIL_VERSION_MICRO 100 #define LIBAVUTIL_VERSION_INT AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \ diff --git a/libavutil/video_hint.c b/libavutil/video_hint.c new file mode 100644 index 0000000000..5730ed6cfb --- /dev/null +++ b/libavutil/video_hint.c @@ -0,0 +1,82 @@ +/* + * Copyright 2023 Elias Carotti + * + * 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 + +#include "avstring.h" +#include "frame.h" +#include "macros.h" +#include "mem.h" +#include "video_hint.h" + +AVVideoHint *av_video_hint_alloc(size_t nb_rects, + size_t *out_size) +{ + struct TestStruct { + AVVideoHint hint; + AVVideoRect rect; + }; + const size_t rect_offset = offsetof(struct TestStruct, rect); + size_t size = rect_offset; + AVVideoHint *hint; + + *out_size = 0; + if (nb_rects > (SIZE_MAX - size) / sizeof(AVVideoRect)) + return NULL; + size += sizeof(AVVideoRect) * nb_rects; + + hint = av_mallocz(size); + if (!hint) + return NULL; + + hint->nb_rects = nb_rects; + hint->rect_offset = rect_offset; + hint->rect_size = sizeof(AVVideoRect); + + *out_size = size; + + return hint; +} + +AVVideoHint *av_video_hint_create_side_data(AVFrame *frame, + size_t nb_rects) +{ + AVVideoHint *hint; + AVBufferRef *buf; + size_t size = 0; + + hint = av_video_hint_alloc(nb_rects, &size); + if (!hint) + return NULL; + + buf = av_buffer_create((uint8_t *)hint, size, NULL, NULL, 0); + if (!buf) { + av_freep(&hint); + return NULL; + } + + if (!av_frame_new_side_data_from_buf(frame, AV_FRAME_DATA_VIDEO_HINT, buf)) { + av_buffer_unref(&buf); + return NULL; + } + + return hint; +} + diff --git a/libavutil/video_hint.h b/libavutil/video_hint.h new file mode 100644 index 0000000000..0442d635c9 --- /dev/null +++ b/libavutil/video_hint.h @@ -0,0 +1,105 @@ +/** + * Copyright 2023 Elias Carotti + * + * 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_VIDEO_HINT_H +#define AVUTIL_VIDEO_HINT_H + +#include +#include +#include "libavutil/avassert.h" +#include "libavutil/frame.h" + +typedef struct AVVideoRect { + uint32_t x, y; + uint32_t width, height; +} AVVideoRect; + +typedef enum AVVideoHintType { + /* rectangled delimit the constant areas (unchanged), default is changed */ + AV_VIDEO_HINT_CONSTANT, + + /* rectangled delimit the constant areas (changed), default is not changed */ + AV_VIDEO_HINT_CHANGED, +} AVVideoHintType; + +typedef struct AVVideoHint { + /** + * Number of AVVideoRect present. + * + * May be 0, in which case no per-rectangle information is present. In this + * case the values of rect_offset / rect_size are unspecified and should + * not be accessed. + */ + size_t nb_rects; + + /** + * Offset in bytes from the beginning of this structure at which the array + * of AVVideoRect starts. + */ + size_t rect_offset; + + /** + * Size in bytes of AVVideoRect. + */ + size_t rect_size; + + AVVideoHintType type; +} AVVideoHint; + +static av_always_inline AVVideoRect* +av_video_hint_rects(const AVVideoHint *hints) { + return (AVVideoRect *)((uint8_t *)hints + hints->rect_offset); } + +static av_always_inline AVVideoRect* +av_video_hint_get_rect(const AVVideoHint *hints, size_t idx) { + return (AVVideoRect *)((uint8_t *)hints + hints->rect_offset + idx +* hints->rect_size); } + +/** + * Allocate memory for the AVVideoHint struct along with an nb_rects-sized + * arrays of AVVideoRect. + * + * The side data contains a list of rectangles for the portions of the frame + * which changed from the last encoded one (and the remainder are assumed to be + * changed), or, alternately (depending on the type parameter) the unchanged + * ones (and the remanining ones are those which changed). + * Macroblocks will thus be hinted either to be P_SKIP-ped or go through the + * regular encoding procedure. + * + * It's responsibility of the caller to fill the AVRects accordingly, and to set + * the proper AVVideoHintType field. + * + * @param out_size if non-NULL, the size in bytes of the resulting data array is + * written here + * + * @return newly allocated AVVideoHint struct (must be freed by the caller using + * av_free()) on success, NULL on memory allocation failure + */ +AVVideoHint *av_video_hint_alloc(size_t nb_rects, + size_t *out_size); +/** + * Same as av_video_hint_alloc(), except newly-allocated AVVideoHint is attached + * as side data of type AV_FRAME_DATA_VIDEO_HINT_INFO to frame. + */ +AVVideoHint *av_video_hint_create_side_data(AVFrame *frame, + size_t nb_rects); + + +#endif /* AVUTIL_VIDEO_HINT_H */ -- 2.34.1