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x264.h
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/*****************************************************************************
* x264.h: x264 public header
*****************************************************************************
* Copyright (C) 2003-2021 x264 project
*
* Authors: Laurent Aimar <fenrir@via.ecp.fr>
* Loren Merritt <lorenm@u.washington.edu>
* Fiona Glaser <fiona@x264.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02111, USA.
*
* This program is also available under a commercial proprietary license.
* For more information, contact us at licensing@x264.com.
*****************************************************************************/
#ifndef X264_X264_H
#define X264_X264_H
#ifdef __cplusplus
extern "C" {
#endif
#if !defined(_STDINT_H) && !defined(_STDINT_H_) && !defined(_STDINT_H_INCLUDED) && !defined(_STDINT) &&\
!defined(_SYS_STDINT_H_) && !defined(_INTTYPES_H) && !defined(_INTTYPES_H_) && !defined(_INTTYPES)
# ifdef _MSC_VER
# pragma message("You must include stdint.h or inttypes.h before x264.h")
# else
# warning You must include stdint.h or inttypes.h before x264.h
# endif
#endif
#include <stdarg.h>
#include "x264_config.h"
#define X264_BUILD 161
#ifdef _WIN32
# define X264_DLL_IMPORT __declspec(dllimport)
# define X264_DLL_EXPORT __declspec(dllexport)
#else
# if defined(__GNUC__) && (__GNUC__ >= 4)
# define X264_DLL_IMPORT
# define X264_DLL_EXPORT __attribute__((visibility("default")))
# else
# define X264_DLL_IMPORT
# define X264_DLL_EXPORT
# endif
#endif
/* Application developers planning to link against a shared library version of
* libx264 from a Microsoft Visual Studio or similar development environment
* will need to define X264_API_IMPORTS before including this header.
* This clause does not apply to MinGW, similar development environments, or non
* Windows platforms. */
#ifdef X264_API_IMPORTS
# define X264_API X264_DLL_IMPORT
#else
# ifdef X264_API_EXPORTS
# define X264_API X264_DLL_EXPORT
# else
# define X264_API
# endif
#endif
/* x264_t:
* opaque handler for encoder */
typedef struct x264_t x264_t;
/****************************************************************************
* NAL structure and functions
****************************************************************************/
enum nal_unit_type_e
{
NAL_UNKNOWN = 0,
NAL_SLICE = 1,
NAL_SLICE_DPA = 2,
NAL_SLICE_DPB = 3,
NAL_SLICE_DPC = 4,
NAL_SLICE_IDR = 5, /* ref_idc != 0 */
NAL_SEI = 6, /* ref_idc == 0 */
NAL_SPS = 7,
NAL_PPS = 8,
NAL_AUD = 9,
NAL_FILLER = 12,
/* ref_idc == 0 for 6,9,10,11,12 */
};
enum nal_priority_e
{
NAL_PRIORITY_DISPOSABLE = 0,
NAL_PRIORITY_LOW = 1,
NAL_PRIORITY_HIGH = 2,
NAL_PRIORITY_HIGHEST = 3,
};
/* The data within the payload is already NAL-encapsulated; the ref_idc and type
* are merely in the struct for easy access by the calling application.
* All data returned in an x264_nal_t, including the data in p_payload, is no longer
* valid after the next call to x264_encoder_encode. Thus it must be used or copied
* before calling x264_encoder_encode or x264_encoder_headers again. */
typedef struct x264_nal_t
{
int i_ref_idc; /* nal_priority_e */
int i_type; /* nal_unit_type_e */
int b_long_startcode;
int i_first_mb; /* If this NAL is a slice, the index of the first MB in the slice. */
int i_last_mb; /* If this NAL is a slice, the index of the last MB in the slice. */
/* Size of payload (including any padding) in bytes. */
int i_payload;
/* If param->b_annexb is set, Annex-B bytestream with startcode.
* Otherwise, startcode is replaced with a 4-byte size.
* This size is the size used in mp4/similar muxing; it is equal to i_payload-4 */
uint8_t *p_payload;
/* Size of padding in bytes. */
int i_padding;
} x264_nal_t;
/****************************************************************************
* Encoder parameters
****************************************************************************/
/* CPU flags */
/* x86 */
#define X264_CPU_MMX (1U<<0)
#define X264_CPU_MMX2 (1U<<1) /* MMX2 aka MMXEXT aka ISSE */
#define X264_CPU_MMXEXT X264_CPU_MMX2
#define X264_CPU_SSE (1U<<2)
#define X264_CPU_SSE2 (1U<<3)
#define X264_CPU_LZCNT (1U<<4)
#define X264_CPU_SSE3 (1U<<5)
#define X264_CPU_SSSE3 (1U<<6)
#define X264_CPU_SSE4 (1U<<7) /* SSE4.1 */
#define X264_CPU_SSE42 (1U<<8) /* SSE4.2 */
#define X264_CPU_AVX (1U<<9) /* Requires OS support even if YMM registers aren't used */
#define X264_CPU_XOP (1U<<10) /* AMD XOP */
#define X264_CPU_FMA4 (1U<<11) /* AMD FMA4 */
#define X264_CPU_FMA3 (1U<<12)
#define X264_CPU_BMI1 (1U<<13)
#define X264_CPU_BMI2 (1U<<14)
#define X264_CPU_AVX2 (1U<<15)
#define X264_CPU_AVX512 (1U<<16) /* AVX-512 {F, CD, BW, DQ, VL}, requires OS support */
/* x86 modifiers */
#define X264_CPU_CACHELINE_32 (1U<<17) /* avoid memory loads that span the border between two cachelines */
#define X264_CPU_CACHELINE_64 (1U<<18) /* 32/64 is the size of a cacheline in bytes */
#define X264_CPU_SSE2_IS_SLOW (1U<<19) /* avoid most SSE2 functions on Athlon64 */
#define X264_CPU_SSE2_IS_FAST (1U<<20) /* a few functions are only faster on Core2 and Phenom */
#define X264_CPU_SLOW_SHUFFLE (1U<<21) /* The Conroe has a slow shuffle unit (relative to overall SSE performance) */
#define X264_CPU_STACK_MOD4 (1U<<22) /* if stack is only mod4 and not mod16 */
#define X264_CPU_SLOW_ATOM (1U<<23) /* The Atom is terrible: slow SSE unaligned loads, slow
* SIMD multiplies, slow SIMD variable shifts, slow pshufb,
* cacheline split penalties -- gather everything here that
* isn't shared by other CPUs to avoid making half a dozen
* new SLOW flags. */
#define X264_CPU_SLOW_PSHUFB (1U<<24) /* such as on the Intel Atom */
#define X264_CPU_SLOW_PALIGNR (1U<<25) /* such as on the AMD Bobcat */
/* PowerPC */
#define X264_CPU_ALTIVEC 0x0000001U
/* ARM and AArch64 */
#define X264_CPU_ARMV6 0x0000001U
#define X264_CPU_NEON 0x0000002U /* ARM NEON */
#define X264_CPU_FAST_NEON_MRC 0x0000004U /* Transfer from NEON to ARM register is fast (Cortex-A9) */
#define X264_CPU_ARMV8 0x0000008U
/* MIPS */
#define X264_CPU_MSA 0x0000001U /* MIPS MSA */
/* Analyse flags */
#define X264_ANALYSE_I4x4 0x0001U /* Analyse i4x4 */
#define X264_ANALYSE_I8x8 0x0002U /* Analyse i8x8 (requires 8x8 transform) */
#define X264_ANALYSE_PSUB16x16 0x0010U /* Analyse p16x8, p8x16 and p8x8 */
#define X264_ANALYSE_PSUB8x8 0x0020U /* Analyse p8x4, p4x8, p4x4 */
#define X264_ANALYSE_BSUB16x16 0x0100U /* Analyse b16x8, b8x16 and b8x8 */
#define X264_DIRECT_PRED_NONE 0
#define X264_DIRECT_PRED_SPATIAL 1
#define X264_DIRECT_PRED_TEMPORAL 2
#define X264_DIRECT_PRED_AUTO 3
#define X264_ME_DIA 0
#define X264_ME_HEX 1
#define X264_ME_UMH 2
#define X264_ME_ESA 3
#define X264_ME_TESA 4
#define X264_CQM_FLAT 0
#define X264_CQM_JVT 1
#define X264_CQM_CUSTOM 2
#define X264_RC_CQP 0
#define X264_RC_CRF 1
#define X264_RC_ABR 2
#define X264_QP_AUTO 0
#define X264_AQ_NONE 0
#define X264_AQ_VARIANCE 1
#define X264_AQ_AUTOVARIANCE 2
#define X264_AQ_AUTOVARIANCE_BIASED 3
#define X264_B_ADAPT_NONE 0
#define X264_B_ADAPT_FAST 1
#define X264_B_ADAPT_TRELLIS 2
#define X264_WEIGHTP_NONE 0
#define X264_WEIGHTP_SIMPLE 1
#define X264_WEIGHTP_SMART 2
#define X264_B_PYRAMID_NONE 0
#define X264_B_PYRAMID_STRICT 1
#define X264_B_PYRAMID_NORMAL 2
#define X264_KEYINT_MIN_AUTO 0
#define X264_KEYINT_MAX_INFINITE (1<<30)
#define X264_LEVEL_IDC_AUTO (-1)
/* AVC-Intra flavors */
#define X264_AVCINTRA_FLAVOR_PANASONIC 0
#define X264_AVCINTRA_FLAVOR_SONY 1
static const char * const x264_direct_pred_names[] = { "none", "spatial", "temporal", "auto", 0 };
static const char * const x264_motion_est_names[] = { "dia", "hex", "umh", "esa", "tesa", 0 };
static const char * const x264_b_pyramid_names[] = { "none", "strict", "normal", 0 };
static const char * const x264_overscan_names[] = { "undef", "show", "crop", 0 };
static const char * const x264_vidformat_names[] = { "component", "pal", "ntsc", "secam", "mac", "undef", 0 };
static const char * const x264_fullrange_names[] = { "off", "on", 0 };
static const char * const x264_colorprim_names[] = { "", "bt709", "undef", "", "bt470m", "bt470bg", "smpte170m", "smpte240m", "film", "bt2020", "smpte428",
"smpte431", "smpte432", 0 };
static const char * const x264_transfer_names[] = { "", "bt709", "undef", "", "bt470m", "bt470bg", "smpte170m", "smpte240m", "linear", "log100", "log316",
"iec61966-2-4", "bt1361e", "iec61966-2-1", "bt2020-10", "bt2020-12", "smpte2084", "smpte428", "arib-std-b67", 0 };
static const char * const x264_colmatrix_names[] = { "GBR", "bt709", "undef", "", "fcc", "bt470bg", "smpte170m", "smpte240m", "YCgCo", "bt2020nc", "bt2020c",
"smpte2085", "chroma-derived-nc", "chroma-derived-c", "ICtCp", 0 };
static const char * const x264_nal_hrd_names[] = { "none", "vbr", "cbr", 0 };
static const char * const x264_avcintra_flavor_names[] = { "panasonic", "sony", 0 };
/* Colorspace type */
#define X264_CSP_MASK 0x00ff /* */
#define X264_CSP_NONE 0x0000 /* Invalid mode */
#define X264_CSP_I400 0x0001 /* monochrome 4:0:0 */
#define X264_CSP_I420 0x0002 /* yuv 4:2:0 planar */
#define X264_CSP_YV12 0x0003 /* yvu 4:2:0 planar */
#define X264_CSP_NV12 0x0004 /* yuv 4:2:0, with one y plane and one packed u+v */
#define X264_CSP_NV21 0x0005 /* yuv 4:2:0, with one y plane and one packed v+u */
#define X264_CSP_I422 0x0006 /* yuv 4:2:2 planar */
#define X264_CSP_YV16 0x0007 /* yvu 4:2:2 planar */
#define X264_CSP_NV16 0x0008 /* yuv 4:2:2, with one y plane and one packed u+v */
#define X264_CSP_YUYV 0x0009 /* yuyv 4:2:2 packed */
#define X264_CSP_UYVY 0x000a /* uyvy 4:2:2 packed */
#define X264_CSP_V210 0x000b /* 10-bit yuv 4:2:2 packed in 32 */
#define X264_CSP_I444 0x000c /* yuv 4:4:4 planar */
#define X264_CSP_YV24 0x000d /* yvu 4:4:4 planar */
#define X264_CSP_BGR 0x000e /* packed bgr 24bits */
#define X264_CSP_BGRA 0x000f /* packed bgr 32bits */
#define X264_CSP_RGB 0x0010 /* packed rgb 24bits */
#define X264_CSP_MAX 0x0011 /* end of list */
#define X264_CSP_VFLIP 0x1000 /* the csp is vertically flipped */
#define X264_CSP_HIGH_DEPTH 0x2000 /* the csp has a depth of 16 bits per pixel component */
/* Slice type */
#define X264_TYPE_AUTO 0x0000 /* Let x264 choose the right type */
#define X264_TYPE_IDR 0x0001
#define X264_TYPE_I 0x0002
#define X264_TYPE_P 0x0003
#define X264_TYPE_BREF 0x0004 /* Non-disposable B-frame */
#define X264_TYPE_B 0x0005
#define X264_TYPE_KEYFRAME 0x0006 /* IDR or I depending on b_open_gop option */
#define IS_X264_TYPE_I(x) ((x)==X264_TYPE_I || (x)==X264_TYPE_IDR || (x)==X264_TYPE_KEYFRAME)
#define IS_X264_TYPE_B(x) ((x)==X264_TYPE_B || (x)==X264_TYPE_BREF)
/* Log level */
#define X264_LOG_NONE (-1)
#define X264_LOG_ERROR 0
#define X264_LOG_WARNING 1
#define X264_LOG_INFO 2
#define X264_LOG_DEBUG 3
/* Threading */
#define X264_THREADS_AUTO 0 /* Automatically select optimal number of threads */
#define X264_SYNC_LOOKAHEAD_AUTO (-1) /* Automatically select optimal lookahead thread buffer size */
/* HRD */
#define X264_NAL_HRD_NONE 0
#define X264_NAL_HRD_VBR 1
#define X264_NAL_HRD_CBR 2
/* Zones: override ratecontrol or other options for specific sections of the video.
* See x264_encoder_reconfig() for which options can be changed.
* If zones overlap, whichever comes later in the list takes precedence. */
typedef struct x264_zone_t
{
int i_start, i_end; /* range of frame numbers */
int b_force_qp; /* whether to use qp vs bitrate factor */
int i_qp;
float f_bitrate_factor;
struct x264_param_t *param;
} x264_zone_t;
/* Auto VBV*/
#define X264_VBV_MAXRATE_HIGH444 -5 /* Set the VBV maxrate to fit in the target level of High 4:4:4 Predictive Profile */
#define X264_VBV_MAXRATE_HIGH422 -4 /* Set the VBV maxrate to fit in the target level of High 4:2:2 Profile */
#define X264_VBV_MAXRATE_HIGH10 -3 /* Set the VBV maxrate to fit in the target level of High 10 Profile */
#define X264_VBV_MAXRATE_HIGH -2 /* Set the VBV maxrate to fit in the target level of High Profile */
#define X264_VBV_MAXRATE_MAIN -1 /* Set the VBV maxrate to fit in the target level of Main Profile */
#define X264_VBV_BUFSIZE_HIGH444 -5 /* Set the VBV bufsize to fit in the target level of High 4:4:4 Predictive Profile */
#define X264_VBV_BUFSIZE_HIGH422 -4 /* Set the VBV bufsize to fit in the target level of High 4:2:2 Profile */
#define X264_VBV_BUFSIZE_HIGH10 -3 /* Set the VBV bufsize to fit in the target level of High 10 Profile */
#define X264_VBV_BUFSIZE_HIGH -2 /* Set the VBV bufsize to fit in the target level of High Profile */
#define X264_VBV_BUFSIZE_MAIN -1 /* Set the VBV bufsize to fit in the target level of Main Profile */
typedef struct x264_param_t
{
/* CPU flags */
uint32_t cpu;
int i_threads; /* encode multiple frames in parallel */
int i_lookahead_threads; /* multiple threads for lookahead analysis */
int b_sliced_threads; /* Whether to use slice-based threading. */
int b_deterministic; /* whether to allow non-deterministic optimizations when threaded */
int b_cpu_independent; /* force canonical behavior rather than cpu-dependent optimal algorithms */
int i_sync_lookahead; /* threaded lookahead buffer */
/* Video Properties */
int i_width;
int i_height;
int i_csp; /* CSP of encoded bitstream */
int i_bitdepth;
int i_level_idc;
int b_level_force; /* force ref etc. for level */
int i_profile;
int b_profile_force; /* do not automatically decrease profile settings even if not needed */
int i_frame_total; /* number of frames to encode if known, else 0 */
/* NAL HRD
* Uses Buffering and Picture Timing SEIs to signal HRD
* The HRD in H.264 was not designed with VFR in mind.
* It is therefore not recommendeded to use NAL HRD with VFR.
* Furthermore, reconfiguring the VBV (via x264_encoder_reconfig)
* will currently generate invalid HRD. */
int i_nal_hrd;
struct
{
/* they will be reduced to be 0 < x <= 65535 and prime */
int i_sar_height;
int i_sar_width;
int i_overscan; /* 0=undef, 1=no overscan, 2=overscan */
/* see h264 annex E for the values of the following */
int i_vidformat;
int b_fullrange;
int i_colorprim;
int i_transfer;
int i_colmatrix;
int i_chroma_loc; /* both top & bottom */
} vui;
/* Bitstream parameters */
int i_frame_reference; /* Maximum number of reference frames */
int i_dpb_size; /* Force a DPB size larger than that implied by B-frames and reference frames.
* Useful in combination with interactive error resilience. */
int i_keyint_max; /* Force an IDR keyframe at this interval */
int i_keyint_min; /* Scenecuts closer together than this are coded as I, not IDR. */
int i_scenecut_threshold; /* how aggressively to insert extra I frames */
int b_intra_refresh; /* Whether or not to use periodic intra refresh instead of IDR frames. */
int i_bframe; /* how many b-frame between 2 references pictures */
int i_bframe_adaptive;
int i_bframe_bias;
int i_bframe_pyramid; /* Keep some B-frames as references: 0=off, 1=strict hierarchical, 2=normal */
int b_open_gop;
int b_bluray_compat;
int i_avcintra_class;
int i_avcintra_flavor;
int b_deblocking_filter;
int i_deblocking_filter_alphac0; /* [-6, 6] -6 light filter, 6 strong */
int i_deblocking_filter_beta; /* [-6, 6] idem */
int b_cabac;
int i_cabac_init_idc;
int b_interlaced;
int b_constrained_intra;
int i_cqm_preset;
char *psz_cqm_file; /* filename (in UTF-8) of CQM file, JM format */
uint8_t cqm_4iy[16]; /* used only if i_cqm_preset == X264_CQM_CUSTOM */
uint8_t cqm_4py[16];
uint8_t cqm_4ic[16];
uint8_t cqm_4pc[16];
uint8_t cqm_8iy[64];
uint8_t cqm_8py[64];
uint8_t cqm_8ic[64];
uint8_t cqm_8pc[64];
/* Log */
void (*pf_log)( void *, int i_level, const char *psz, va_list );
void *p_log_private;
int i_log_level;
int b_full_recon; /* fully reconstruct frames, even when not necessary for encoding. Implied by psz_dump_yuv */
int b_stylish;
char *psz_dump_yuv; /* filename (in UTF-8) for reconstructed frames */
/* Encoder analyser parameters */
struct
{
unsigned int intra; /* intra partitions */
unsigned int inter; /* inter partitions */
int b_transform_8x8;
int i_weighted_pred; /* weighting for P-frames */
int b_weighted_bipred; /* implicit weighting for B-frames */
int i_direct_mv_pred; /* spatial vs temporal mv prediction */
int i_chroma_qp_offset;
int i_me_method; /* motion estimation algorithm to use (X264_ME_*) */
int i_me_range; /* integer pixel motion estimation search range (from predicted mv) */
int i_mv_range; /* maximum length of a mv (in pixels). -1 = auto, based on level */
int i_mv_range_thread; /* minimum space between threads. -1 = auto, based on number of threads. */
int i_subpel_refine; /* subpixel motion estimation quality */
int b_chroma_me; /* chroma ME for subpel and mode decision in P-frames */
int b_mixed_references; /* allow each mb partition to have its own reference number */
int i_trellis; /* trellis RD quantization */
int b_fast_pskip; /* early SKIP detection on P-frames */
int b_dct_decimate; /* transform coefficient thresholding on P-frames */
int i_noise_reduction; /* adaptive pseudo-deadzone */
float f_psy_rd; /* Psy RD strength */
float f_psy_trellis; /* Psy trellis strength */
int b_psy; /* Toggle all psy optimizations */
int b_mb_info; /* Use input mb_info data in x264_picture_t */
int b_mb_info_update; /* Update the values in mb_info according to the results of encoding. */
/* the deadzone size that will be used in luma quantization */
int i_luma_deadzone[2]; /* {inter, intra} */
int b_psnr; /* compute and print PSNR stats */
int b_ssim; /* compute and print SSIM stats */
} analyse;
/* Rate control parameters */
struct
{
int i_rc_method; /* X264_RC_* */
int i_qp_constant; /* 0=lossless */
int i_qp_min; /* min allowed QP value */
int i_qp_max; /* max allowed QP value */
int i_qp_step; /* max QP step between frames */
int i_bitrate;
float f_rf_constant; /* 1pass VBR, nominal QP */
float f_rf_constant_max; /* In CRF mode, maximum CRF as caused by VBV */
float f_rate_tolerance;
int i_vbv_max_bitrate;
int i_vbv_buffer_size;
float f_vbv_buffer_init; /* <=1: fraction of buffer_size. >1: kbit */
float f_ip_factor;
float f_pb_factor;
/* VBV filler: force CBR VBV and use filler bytes to ensure hard-CBR.
* Implied by NAL-HRD CBR. */
int b_filler;
int i_aq_mode; /* psy adaptive QP. (X264_AQ_*) */
float f_aq_strength;
int b_mb_tree; /* Macroblock-tree ratecontrol. */
int i_lookahead;
/* 2pass */
int b_stat_write; /* Enable stat writing in psz_stat_out */
char *psz_stat_out; /* output filename (in UTF-8) of the 2pass stats file */
int b_stat_read; /* Read stat from psz_stat_in and use it */
char *psz_stat_in; /* input filename (in UTF-8) of the 2pass stats file */
/* 2pass params (same as ffmpeg ones) */
float f_qcompress; /* 0.0 => cbr, 1.0 => constant qp */
float f_qblur; /* temporally blur quants */
float f_complexity_blur; /* temporally blur complexity */
x264_zone_t *zones; /* ratecontrol overrides */
int i_zones; /* number of zone_t's */
char *psz_zones; /* alternate method of specifying zones */
} rc;
/* Cropping Rectangle parameters: added to those implicitly defined by
non-mod16 video resolutions. */
struct
{
int i_left;
int i_top;
int i_right;
int i_bottom;
} crop_rect;
/* frame packing arrangement flag */
int i_frame_packing;
/* alternative transfer SEI */
int i_alternative_transfer;
/* Muxing parameters */
int b_aud; /* generate access unit delimiters */
int b_repeat_headers; /* put SPS/PPS before each keyframe */
int b_annexb; /* if set, place start codes (4 bytes) before NAL units,
* otherwise place size (4 bytes) before NAL units. */
int i_sps_id; /* SPS and PPS id number */
int b_vfr_input; /* VFR input. If 1, use timebase and timestamps for ratecontrol purposes.
* If 0, use fps only. */
int b_pulldown; /* use explicity set timebase for CFR */
uint32_t i_fps_num;
uint32_t i_fps_den;
int b_accurate_fps;
uint32_t i_timebase_num; /* Timebase numerator */
uint32_t i_timebase_den; /* Timebase denominator */
int b_tff;
/* Pulldown:
* The correct pic_struct must be passed with each input frame.
* The input timebase should be the timebase corresponding to the output framerate. This should be constant.
* e.g. for 3:2 pulldown timebase should be 1001/30000
* The PTS passed with each frame must be the PTS of the frame after pulldown is applied.
* Frame doubling and tripling require b_vfr_input set to zero (see H.264 Table D-1)
*
* Pulldown changes are not clearly defined in H.264. Therefore, it is the calling app's responsibility to manage this.
*/
int b_pic_struct;
/* Fake Interlaced.
*
* Used only when b_interlaced=0. Setting this flag makes it possible to flag the stream as PAFF interlaced yet
* encode all frames progessively. It is useful for encoding 25p and 30p Blu-Ray streams.
*/
int b_fake_interlaced;
/* Don't optimize header parameters based on video content, e.g. ensure that splitting an input video, compressing
* each part, and stitching them back together will result in identical SPS/PPS. This is necessary for stitching
* with container formats that don't allow multiple SPS/PPS. */
int b_stitchable;
int b_opencl; /* use OpenCL when available */
int i_opencl_device; /* specify count of GPU devices to skip, for CLI users */
void *opencl_device_id; /* pass explicit cl_device_id as void*, for API users */
char *psz_clbin_file; /* filename (in UTF-8) of the compiled OpenCL kernel cache file */
/* Slicing parameters */
int i_slice_max_size; /* Max size per slice in bytes; includes estimated NAL overhead. */
int i_slice_max_mbs; /* Max number of MBs per slice; overrides i_slice_count. */
int i_slice_min_mbs; /* Min number of MBs per slice */
int i_slice_count; /* Number of slices per frame: forces rectangular slices. */
int i_slice_count_max; /* Absolute cap on slices per frame; stops applying slice-max-size
* and slice-max-mbs if this is reached. */
/* Optional callback for freeing this x264_param_t when it is done being used.
* Only used when the x264_param_t sits in memory for an indefinite period of time,
* i.e. when an x264_param_t is passed to x264_t in an x264_picture_t or in zones.
* Not used when x264_encoder_reconfig is called directly. */
void (*param_free)( void* );
/* Optional low-level callback for low-latency encoding. Called for each output NAL unit
* immediately after the NAL unit is finished encoding. This allows the calling application
* to begin processing video data (e.g. by sending packets over a network) before the frame
* is done encoding.
*
* This callback MUST do the following in order to work correctly:
* 1) Have available an output buffer of at least size nal->i_payload*3/2 + 5 + 64.
* 2) Call x264_nal_encode( h, dst, nal ), where dst is the output buffer.
* After these steps, the content of nal is valid and can be used in the same way as if
* the NAL unit were output by x264_encoder_encode.
*
* This does not need to be synchronous with the encoding process: the data pointed to
* by nal (both before and after x264_nal_encode) will remain valid until the next
* x264_encoder_encode call. The callback must be re-entrant.
*
* This callback does not work with frame-based threads; threads must be disabled
* or sliced-threads enabled. This callback also does not work as one would expect
* with HRD -- since the buffering period SEI cannot be calculated until the frame
* is finished encoding, it will not be sent via this callback.
*
* Note also that the NALs are not necessarily returned in order when sliced threads is
* enabled. Accordingly, the variable i_first_mb and i_last_mb are available in
* x264_nal_t to help the calling application reorder the slices if necessary.
*
* When this callback is enabled, x264_encoder_encode does not return valid NALs;
* the calling application is expected to acquire all output NALs through the callback.
*
* It is generally sensible to combine this callback with a use of slice-max-mbs or
* slice-max-size.
*
* The opaque pointer is the opaque pointer from the input frame associated with this
* NAL unit. This helps distinguish between nalu_process calls from different sources,
* e.g. if doing multiple encodes in one process.
*/
void (*nalu_process)( x264_t *h, x264_nal_t *nal, void *opaque );
/* For internal use only */
void *opaque;
} x264_param_t;
X264_API void x264_nal_encode( x264_t *h, uint8_t *dst, x264_nal_t *nal );
/****************************************************************************
* H.264 level restriction information
****************************************************************************/
typedef struct x264_level_t
{
uint8_t level_idc;
int32_t mbps; /* max macroblock processing rate (macroblocks/sec) */
int32_t frame_size; /* max frame size (macroblocks) */
int32_t dpb; /* max decoded picture buffer (mbs) */
int32_t bitrate; /* max bitrate (kbit/sec) */
int32_t cpb; /* max vbv buffer (kbit) */
uint16_t mv_range; /* max vertical mv component range (pixels) */
uint8_t mvs_per_2mb; /* max mvs per 2 consecutive mbs. */
uint8_t slice_rate; /* ?? */
uint8_t mincr; /* min compression ratio */
uint8_t bipred8x8; /* limit bipred to >=8x8 */
uint8_t direct8x8; /* limit b_direct to >=8x8 */
uint8_t frame_only; /* forbid interlacing */
} x264_level_t;
/* all of the levels defined in the standard, terminated by .level_idc=0 */
X264_API extern const x264_level_t x264_levels[];
/****************************************************************************
* Basic parameter handling functions
****************************************************************************/
/* x264_param_default:
* fill x264_param_t with default values and do CPU detection */
X264_API void x264_param_default( x264_param_t * );
/* x264_param_parse:
* set one parameter by name.
* returns 0 on success, or returns one of the following errors.
* note: BAD_VALUE occurs only if it can't even parse the value,
* numerical range is not checked until x264_encoder_open() or
* x264_encoder_reconfig().
* value=NULL means "true" for boolean options, but is a BAD_VALUE for non-booleans.
* can allocate memory which should be freed by call of x264_param_cleanup. */
#define X264_PARAM_BAD_NAME (-1)
#define X264_PARAM_BAD_VALUE (-2)
#define X264_PARAM_ALLOC_FAILED (-3)
X264_API int x264_param_parse( x264_param_t *, const char *name, const char *value );
/* x264_param_cleanup:
* Cleans up and frees allocated members of x264_param_t.
* This *does not* free the x264_param_t itself, as it may exist on the
* stack. It only frees any members of the struct that were allocated by
* x264 itself, in e.g. x264_param_parse(). */
X264_API void x264_param_cleanup( x264_param_t *param );
/****************************************************************************
* Advanced parameter handling functions
****************************************************************************/
/* These functions expose the full power of x264's preset-tune-profile system for
* easy adjustment of large numbers of internal parameters.
*
* In order to replicate x264CLI's option handling, these functions MUST be called
* in the following order:
* 1) x264_param_default_preset
* 2) Custom user options (via param_parse or directly assigned variables)
* 3) x264_param_apply_fastfirstpass
* 4) x264_param_apply_profile
*
* Additionally, x264CLI does not apply step 3 if the preset chosen is "placebo"
* or --slow-firstpass is set. */
/* x264_param_default_preset:
* The same as x264_param_default, but also use the passed preset and tune
* to modify the default settings.
* (either can be NULL, which implies no preset or no tune, respectively)
*
* Currently available presets are, ordered from fastest to slowest: */
static const char * const x264_preset_names[] = { "ultrafast", "superfast", "veryfast", "faster", "fast", "medium", "slow", "slower", "veryslow", "placebo", 0 };
/* The presets can also be indexed numerically, as in:
* x264_param_default_preset( ¶m, "3", ... )
* with ultrafast mapping to "0" and placebo mapping to "9". This mapping may
* of course change if new presets are added in between, but will always be
* ordered from fastest to slowest.
*
* Warning: the speed of these presets scales dramatically. Ultrafast is a full
* 100 times faster than placebo!
*
* Currently available tunings are: */
static const char * const x264_tune_names[] = { "film", "animation", "grain", "stillimage", "psnr", "ssim", "fastdecode", "zerolatency", 0 };
/* Multiple tunings can be used if separated by a delimiter in ",./-+",
* however multiple psy tunings cannot be used.
* film, animation, grain, stillimage, psnr, and ssim are psy tunings.
*
* returns 0 on success, negative on failure (e.g. invalid preset/tune name). */
X264_API int x264_param_default_preset( x264_param_t *, const char *preset, const char *tune );
/* x264_param_apply_fastfirstpass:
* If first-pass mode is set (rc.b_stat_read == 0, rc.b_stat_write == 1),
* modify the encoder settings to disable options generally not useful on
* the first pass. */
X264_API void x264_param_apply_fastfirstpass( x264_param_t * );
/* x264_param_apply_profile:
* Applies the restrictions of the given profile.
* Currently available profiles are, from most to least restrictive: */
static const char * const x264_profile_names[] = { "baseline", "main", "high", "high10", "high422", "high444", 0 };
/* (can be NULL, in which case the function will do nothing)
*
* Does NOT guarantee that the given profile will be used: if the restrictions
* of "High" are applied to settings that are already Baseline-compatible, the
* stream will remain baseline. In short, it does not increase settings, only
* decrease them.
*
* returns 0 on success, negative on failure (e.g. invalid profile name). */
X264_API int x264_param_apply_profile( x264_param_t *, const char *profile );
/****************************************************************************
* Picture structures and functions
****************************************************************************/
/* x264_chroma_format:
* Specifies the chroma formats that x264 supports encoding. When this
* value is non-zero, then it represents a X264_CSP_* that is the only
* chroma format that x264 supports encoding. If the value is 0 then
* there are no restrictions. */
X264_API extern const int x264_chroma_format;
enum pic_struct_e
{
PIC_STRUCT_AUTO = 0, // automatically decide (default)
PIC_STRUCT_PROGRESSIVE = 1, // progressive frame
// "TOP" and "BOTTOM" are not supported in x264 (PAFF only)
PIC_STRUCT_TOP_BOTTOM = 4, // top field followed by bottom
PIC_STRUCT_BOTTOM_TOP = 5, // bottom field followed by top
PIC_STRUCT_TOP_BOTTOM_TOP = 6, // top field, bottom field, top field repeated
PIC_STRUCT_BOTTOM_TOP_BOTTOM = 7, // bottom field, top field, bottom field repeated
PIC_STRUCT_DOUBLE = 8, // double frame
PIC_STRUCT_TRIPLE = 9, // triple frame
};
typedef struct x264_hrd_t
{
double cpb_initial_arrival_time;
double cpb_final_arrival_time;
double cpb_removal_time;
double dpb_output_time;
} x264_hrd_t;
/* Arbitrary user SEI:
* Payload size is in bytes and the payload pointer must be valid.
* Payload types and syntax can be found in Annex D of the H.264 Specification.
* SEI payload alignment bits as described in Annex D must be included at the
* end of the payload if needed.
* The payload should not be NAL-encapsulated.
* Payloads are written first in order of input, apart from in the case when HRD
* is enabled where payloads are written after the Buffering Period SEI. */
typedef struct x264_sei_payload_t
{
int payload_size;
int payload_type;
uint8_t *payload;
} x264_sei_payload_t;
typedef struct x264_sei_t
{
int num_payloads;
x264_sei_payload_t *payloads;
/* In: optional callback to free each payload AND x264_sei_payload_t when used. */
void (*sei_free)( void* );
} x264_sei_t;
typedef struct x264_image_t
{
int i_csp; /* Colorspace */
int i_plane; /* Number of image planes */
int i_stride[4]; /* Strides for each plane */
uint8_t *plane[4]; /* Pointers to each plane */
} x264_image_t;
typedef struct x264_image_properties_t
{
/* All arrays of data here are ordered as follows:
* each array contains one offset per macroblock, in raster scan order. In interlaced
* mode, top-field MBs and bottom-field MBs are interleaved at the row level.
* Macroblocks are 16x16 blocks of pixels (with respect to the luma plane). For the
* purposes of calculating the number of macroblocks, width and height are rounded up to
* the nearest 16. If in interlaced mode, height is rounded up to the nearest 32 instead. */
/* In: an array of quantizer offsets to be applied to this image during encoding.
* These are added on top of the decisions made by x264.
* Offsets can be fractional; they are added before QPs are rounded to integer.
* Adaptive quantization must be enabled to use this feature. Behavior if quant
* offsets differ between encoding passes is undefined. */
float *quant_offsets;
/* In: optional callback to free quant_offsets when used.
* Useful if one wants to use a different quant_offset array for each frame. */
void (*quant_offsets_free)( void* );
/* In: optional array of flags for each macroblock.
* Allows specifying additional information for the encoder such as which macroblocks
* remain unchanged. Usable flags are listed below.
* x264_param_t.analyse.b_mb_info must be set to use this, since x264 needs to track
* extra data internally to make full use of this information.
*
* Out: if b_mb_info_update is set, x264 will update this array as a result of encoding.
*
* For "MBINFO_CONSTANT", it will remove this flag on any macroblock whose decoded
* pixels have changed. This can be useful for e.g. noting which areas of the
* frame need to actually be blitted. Note: this intentionally ignores the effects
* of deblocking for the current frame, which should be fine unless one needs exact
* pixel-perfect accuracy.
*
* Results for MBINFO_CONSTANT are currently only set for P-frames, and are not
* guaranteed to enumerate all blocks which haven't changed. (There may be false
* negatives, but no false positives.)
*/
uint8_t *mb_info;
/* In: optional callback to free mb_info when used. */
void (*mb_info_free)( void* );
/* The macroblock is constant and remains unchanged from the previous frame. */
#define X264_MBINFO_CONSTANT (1U<<0)
/* More flags may be added in the future. */
/* Out: SSIM of the the frame luma (if x264_param_t.b_ssim is set) */
double f_ssim;
/* Out: Average PSNR of the frame (if x264_param_t.b_psnr is set) */
double f_psnr_avg;
/* Out: PSNR of Y, U, and V (if x264_param_t.b_psnr is set) */
double f_psnr[3];
/* Out: Average effective CRF of the encoded frame */
double f_crf_avg;
} x264_image_properties_t;
typedef struct x264_picture_t
{
/* In: force picture type (if not auto)
* If x264 encoding parameters are violated in the forcing of picture types,
* x264 will correct the input picture type and log a warning.
* Out: type of the picture encoded */
int i_type;
/* In: force quantizer for != X264_QP_AUTO */
int i_qpplus1;
/* In: pic_struct, for pulldown/doubling/etc...used only if b_pic_struct=1.
* use pic_struct_e for pic_struct inputs
* Out: pic_struct element associated with frame */
int i_pic_struct;
/* Out: whether this frame is a keyframe. Important when using modes that result in
* SEI recovery points being used instead of IDR frames. */
int b_keyframe;
/* In: user pts, Out: pts of encoded picture (user)*/
int64_t i_pts;
/* Out: frame dts. When the pts of the first frame is close to zero,
* initial frames may have a negative dts which must be dealt with by any muxer */
int64_t i_dts;
/* In: custom encoding parameters to be set from this frame forwards
(in coded order, not display order). If NULL, continue using
parameters from the previous frame. Some parameters, such as
aspect ratio, can only be changed per-GOP due to the limitations
of H.264 itself; in this case, the caller must force an IDR frame
if it needs the changed parameter to apply immediately. */
x264_param_t *param;
/* In: raw image data */
/* Out: reconstructed image data. x264 may skip part of the reconstruction process,
e.g. deblocking, in frames where it isn't necessary. To force complete
reconstruction, at a small speed cost, set b_full_recon. */
x264_image_t img;
/* In: optional information to modify encoder decisions for this frame
* Out: information about the encoded frame */
x264_image_properties_t prop;
/* Out: HRD timing information. Output only when i_nal_hrd is set. */
x264_hrd_t hrd_timing;
/* In: arbitrary user SEI (e.g subtitles, AFDs) */
x264_sei_t extra_sei;
/* private user data. copied from input to output frames. */
void *opaque;
} x264_picture_t;
/* x264_picture_init:
* initialize an x264_picture_t. Needs to be done if the calling application
* allocates its own x264_picture_t as opposed to using x264_picture_alloc. */
X264_API void x264_picture_init( x264_picture_t *pic );
/* x264_picture_alloc:
* alloc data for a picture. You must call x264_picture_clean on it.
* returns 0 on success, or -1 on malloc failure or invalid colorspace. */
X264_API int x264_picture_alloc( x264_picture_t *pic, int i_csp, int i_width, int i_height );
/* x264_picture_clean:
* free associated resource for a x264_picture_t allocated with
* x264_picture_alloc ONLY */
X264_API void x264_picture_clean( x264_picture_t *pic );
/****************************************************************************
* Encoder functions
****************************************************************************/
/* Force a link error in the case of linking against an incompatible API version.
* Glue #defines exist to force correct macro expansion; the final output of the macro
* is x264_encoder_open_##X264_BUILD (for purposes of dlopen). */
#define x264_encoder_glue1(x,y) x##y
#define x264_encoder_glue2(x,y) x264_encoder_glue1(x,y)
#define x264_encoder_open x264_encoder_glue2(x264_encoder_open_,X264_BUILD)
/* x264_encoder_open:
* create a new encoder handler, all parameters from x264_param_t are copied */
X264_API x264_t *x264_encoder_open( x264_param_t * );
/* x264_encoder_reconfig:
* various parameters from x264_param_t are copied.
* this takes effect immediately, on whichever frame is encoded next;
* due to delay, this may not be the next frame passed to encoder_encode.
* if the change should apply to some particular frame, use x264_picture_t->param instead.
* returns 0 on success, negative on parameter validation error.
* not all parameters can be changed; see the actual function for a detailed breakdown.
*
* since not all parameters can be changed, moving from preset to preset may not always
* fully copy all relevant parameters, but should still work usably in practice. however,
* more so than for other presets, many of the speed shortcuts used in ultrafast cannot be
* switched out of; using reconfig to switch between ultrafast and other presets is not
* recommended without a more fine-grained breakdown of parameters to take this into account. */
X264_API int x264_encoder_reconfig( x264_t *, x264_param_t * );
/* x264_encoder_parameters:
* copies the current internal set of parameters to the pointer provided
* by the caller. useful when the calling application needs to know
* how x264_encoder_open has changed the parameters, or the current state
* of the encoder after multiple x264_encoder_reconfig calls.
* note that the data accessible through pointers in the returned param struct
* (e.g. filenames) should not be modified by the calling application. */
X264_API void x264_encoder_parameters( x264_t *, x264_param_t * );
/* x264_encoder_headers:
* return the SPS and PPS that will be used for the whole stream.
* *pi_nal is the number of NAL units outputted in pp_nal.
* returns the number of bytes in the returned NALs.
* returns negative on error.
* the payloads of all output NALs are guaranteed to be sequential in memory. */
X264_API int x264_encoder_headers( x264_t *, x264_nal_t **pp_nal, int *pi_nal );
/* x264_encoder_encode:
* encode one picture.
* *pi_nal is the number of NAL units outputted in pp_nal.
* returns the number of bytes in the returned NALs.
* returns negative on error and zero if no NAL units returned.
* the payloads of all output NALs are guaranteed to be sequential in memory. */
X264_API int x264_encoder_encode( x264_t *, x264_nal_t **pp_nal, int *pi_nal, x264_picture_t *pic_in, x264_picture_t *pic_out );
/* x264_encoder_close:
* close an encoder handler */
X264_API void x264_encoder_close( x264_t * );
/* x264_encoder_delayed_frames:
* return the number of currently delayed (buffered) frames
* this should be used at the end of the stream, to know when you have all the encoded frames. */
X264_API int x264_encoder_delayed_frames( x264_t * );
/* x264_encoder_maximum_delayed_frames( x264_t * ):
* return the maximum number of delayed (buffered) frames that can occur with the current
* parameters. */
X264_API int x264_encoder_maximum_delayed_frames( x264_t * );
/* x264_encoder_intra_refresh:
* If an intra refresh is not in progress, begin one with the next P-frame.
* If an intra refresh is in progress, begin one as soon as the current one finishes.
* Requires that b_intra_refresh be set.
*
* Useful for interactive streaming where the client can tell the server that packet loss has
* occurred. In this case, keyint can be set to an extremely high value so that intra refreshes
* only occur when calling x264_encoder_intra_refresh.
*
* In multi-pass encoding, if x264_encoder_intra_refresh is called differently in each pass,
* behavior is undefined.
*
* Should not be called during an x264_encoder_encode. */
X264_API void x264_encoder_intra_refresh( x264_t * );
/* x264_encoder_invalidate_reference:
* An interactive error resilience tool, designed for use in a low-latency one-encoder-few-clients
* system. When the client has packet loss or otherwise incorrectly decodes a frame, the encoder
* can be told with this command to "forget" the frame and all frames that depend on it, referencing
* only frames that occurred before the loss. This will force a keyframe if no frames are left to
* reference after the aforementioned "forgetting".
*
* It is strongly recommended to use a large i_dpb_size in this case, which allows the encoder to
* keep around extra, older frames to fall back on in case more recent frames are all invalidated.
* Unlike increasing i_frame_reference, this does not increase the number of frames used for motion
* estimation and thus has no speed impact. It is also recommended to set a very large keyframe
* interval, so that keyframes are not used except as necessary for error recovery.
*
* x264_encoder_invalidate_reference is not currently compatible with the use of B-frames or intra
* refresh.
*
* In multi-pass encoding, if x264_encoder_invalidate_reference is called differently in each pass,