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mirror of https://github.com/FFmpeg/FFmpeg.git synced 2025-08-04 22:03:09 +02:00

avutil: add an API to handle 3D Reference Displays Information

As defined in section G.14.3.2.3 of ITU-T H.265, it's required for proper
signaling of MV-HEVC.

Signed-off-by: James Almer <jamrial@gmail.com>
This commit is contained in:
James Almer
2025-01-31 10:42:19 -03:00
committed by Timo Rothenpieler
parent 3b9dbda49b
commit 80a05bea4f
4 changed files with 218 additions and 1 deletions

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@ -85,6 +85,7 @@ HEADERS = adler32.h \
sha512.h \ sha512.h \
spherical.h \ spherical.h \
stereo3d.h \ stereo3d.h \
tdrdi.h \
threadmessage.h \ threadmessage.h \
time.h \ time.h \
timecode.h \ timecode.h \
@ -179,6 +180,7 @@ OBJS = adler32.o \
slicethread.o \ slicethread.o \
spherical.o \ spherical.o \
stereo3d.o \ stereo3d.o \
tdrdi.o \
threadmessage.o \ threadmessage.o \
time.o \ time.o \
timecode.o \ timecode.o \

51
libavutil/tdrdi.c Normal file
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@ -0,0 +1,51 @@
/*
* 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 <stddef.h>
#include <stdint.h>
#include "mem.h"
#include "tdrdi.h"
AV3DReferenceDisplaysInfo *av_tdrdi_alloc(unsigned int nb_displays, size_t *out_size)
{
struct TestStruct {
AV3DReferenceDisplaysInfo p;
AV3DReferenceDisplay b;
};
const size_t entries_offset = offsetof(struct TestStruct, b);
size_t size = entries_offset;
AV3DReferenceDisplaysInfo *tdrdi;
if (nb_displays > (SIZE_MAX - size) / sizeof(AV3DReferenceDisplay))
return NULL;
size += sizeof(AV3DReferenceDisplay) * nb_displays;
tdrdi = av_mallocz(size);
if (!tdrdi)
return NULL;
tdrdi->num_ref_displays = nb_displays;
tdrdi->entry_size = sizeof(AV3DReferenceDisplay);
tdrdi->entries_offset = entries_offset;
if (out_size)
*out_size = size;
return tdrdi;
}

164
libavutil/tdrdi.h Normal file
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@ -0,0 +1,164 @@
/*
* 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
*/
/**
* @file
* @ingroup lavu_video_3d_reference_displays_info
* Spherical video
*/
#ifndef AVUTIL_TDRDI_H
#define AVUTIL_TDRDI_H
#include <stddef.h>
#include <stdint.h>
#include "libavutil/avassert.h"
/**
* @defgroup lavu_video_3d_reference_displays_info 3D Reference Displays Information
* @ingroup lavu_video
*
* The 3D Reference Displays Information describes information about the reference display
* width(s) and reference viewing distance(s) as well as information about the corresponding
* reference stereo pair(s).
* @{
*/
#define AV_TDRDI_MAX_NUM_REF_DISPLAY 32
/**
* This structure describes information about the reference display width(s) and reference
* viewing distance(s) as well as information about the corresponding reference stereo pair(s).
* See section G.14.3.2.3 of ITU-T H.265 for more information.
*
* @note The struct must be allocated with av_tdrdi_alloc() and
* its size is not a part of the public ABI.
*/
typedef struct AV3DReferenceDisplaysInfo {
/**
* The exponent of the maximum allowable truncation error for
* {exponent,mantissa}_ref_display_width as given by 2<sup>(-prec_ref_display_width)</sup>.
*/
uint8_t prec_ref_display_width;
/**
* A flag to indicate the presence of reference viewing distance.
* If false, the values of prec_ref_viewing_dist, exponent_ref_viewing_distance,
* and mantissa_ref_viewing_distance are undefined.
*/
uint8_t ref_viewing_distance_flag;
/**
* The exponent of the maximum allowable truncation error for
* {exponent,mantissa}_ref_viewing_distance as given by 2<sup>^(-prec_ref_viewing_dist)</sup>.
* The value of prec_ref_viewing_dist shall be in the range of 0 to 31, inclusive.
*/
uint8_t prec_ref_viewing_dist;
/**
* The number of reference displays that are signalled in this struct.
* Allowed range is 1 to 32, inclusive.
*/
uint8_t num_ref_displays;
/**
* Offset in bytes from the beginning of this structure at which the array
* of reference displays starts.
*/
size_t entries_offset;
/**
* Size of each entry in bytes. May not match sizeof(AV3DReferenceDisplay).
*/
size_t entry_size;
} AV3DReferenceDisplaysInfo;
/**
* Data structure for single deference display information.
* It is allocated as a part of AV3DReferenceDisplaysInfo and should be retrieved with
* av_tdrdi_get_display().
*
* sizeof(AV3DReferenceDisplay) is not a part of the ABI and new fields may be
* added to it.
*/
typedef struct AV3DReferenceDisplay {
/**
* The ViewId of the left view of a stereo pair corresponding to the n-th reference display.
*/
uint16_t left_view_id;
/**
* The ViewId of the left view of a stereo pair corresponding to the n-th reference display.
*/
uint16_t right_view_id;
/**
* The exponent part of the reference display width of the n-th reference display.
*/
uint8_t exponent_ref_display_width;
/**
* The mantissa part of the reference display width of the n-th reference display.
*/
uint8_t mantissa_ref_display_width;
/**
* Tthe exponent part of the reference viewing distance of the n-th reference display.
*/
uint8_t exponent_ref_viewing_distance;
/**
* The mantissa part of the reference viewing distance of the n-th reference display.
*/
uint8_t mantissa_ref_viewing_distance;
/**
* An array of flags to indicates that the information about additional horizontal shift of
* the left and right views for the n-th reference display is present.
*/
uint8_t additional_shift_present_flag;
/**
* The recommended additional horizontal shift for a stereo pair corresponding to the n-th
* reference baseline and the n-th reference display.
*/
int16_t num_sample_shift;
} AV3DReferenceDisplay;
static av_always_inline AV3DReferenceDisplay*
av_tdrdi_get_display(AV3DReferenceDisplaysInfo *tdrdi, unsigned int idx)
{
av_assert0(idx < tdrdi->num_ref_displays);
return (AV3DReferenceDisplay *)((uint8_t *)tdrdi + tdrdi->entries_offset +
idx * tdrdi->entry_size);
}
/**
* Allocate a AV3DReferenceDisplaysInfo structure and initialize its fields to default
* values.
*
* @return the newly allocated struct or NULL on failure
*/
AV3DReferenceDisplaysInfo *av_tdrdi_alloc(unsigned int nb_displays, size_t *size);
/**
* @}
*/
#endif /* AVUTIL_TDRDI_H */

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@ -79,7 +79,7 @@
*/ */
#define LIBAVUTIL_VERSION_MAJOR 60 #define LIBAVUTIL_VERSION_MAJOR 60
#define LIBAVUTIL_VERSION_MINOR 3 #define LIBAVUTIL_VERSION_MINOR 4
#define LIBAVUTIL_VERSION_MICRO 100 #define LIBAVUTIL_VERSION_MICRO 100
#define LIBAVUTIL_VERSION_INT AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \ #define LIBAVUTIL_VERSION_INT AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \