OpenH264

目前最常用的264工程师x264;

最近有又有一个开源工程OpenH264,WebRTC再用用,具体工程具体没有详细研究;

编译完成工程后,用h264dec.exe命令行测试解码x264编码的文件,解码后正常显示,也就是说这两个工程编码的格式应该相互兼容;

地址:http://www.openh264.org/faq.html


提供C语言接口和C++接口;

目前网络可以找到的文档相对较少,大概浏览了一下这个工程,觉得还不错;


工程编译Win7:

我在win7上简单编译了一些工程,没有特别需要配置的地方,

1:下载源码,解压;

2:msys进入解压目录,直接执行 make 命令;

3:几分钟后编译完成,在解压目录生成相关exe文件,几个.a文件,和一个libopenh264.dll文件;

4:在目录openh264-1.0.0\codec\build\win32\enc下有VS工程,打开可以编译出控制台程序和相关dll文件夹;生成的文件在\openh264-1.0.0\bin\win32\Debug;

当然其它平台也有相关的工程IDE文件;

5:还有一个方法:进入目录\openh264-1.0.0\testbin,用管理员权限执行 AutoBuild_Windows_VS2008.bat 文件,注意修改文件中的VS路径与计算机上的安装路径一直;

然后编译就可以了,文件在openh264-1.0.0\bin\win32目录中,有debug和release两个文件夹;



示例目录:

OpenSource\openh264\test   //这个目录下有相关的一些示例;

也可以 OpenSource\openh264\codec\build\win32\enc 通过VC打开这个目录,查看更加完整的例子,这个是exe实力,更全面;


以下是工程中的说明文档:


OpenH264_API_v1.0.docx文档

Contents

Encoder Interface Usage: 2

Step#1: create and destroy the encoder 2

Step#2: initialize the encoder 2

Step#3: invoker the encoding 2

Step#4: control the encoding 3

Encoder Option List: 4

Encoder Parameter List: 6

Encoder Return Value: CM_RETURN 9

Encoder Return Value: EVideoFrameType: 9

Decoder Usage: 10

Step#1: create and destroy the decoder 10

Step#2: initialize the decoder 10

Step#3: invoker the decoding 10

Step#4: control the decoding 11

Decoder Option List: 12

Decoder Parameter List: 13

Decoder Usage Example: 13

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Revisions history

Date

Version

Author

Description

12/23/2013

0.1

Sijia Chen, Wayne Liu

Initial version

12/25/2013

0.2

Sijia Chen

Add encoder return value explanation

12/25/2013

0.3

Sijia Chen

Add explanation on range of some parameters in encoder

03/04/2014

0.4

Karina Li

Interface and parameters update

05/23/2014

1.0

Wayne Liu, Karina Li

Update for v1.0 release

 

Encoder Interface Usage:

Step#1: create and destroy the encoder

int  WelsCreateSVCEncoder(ISVCEncoder** ppEncoder);

void WelsDestroySVCEncoder(ISVCEncoder* pEncoder);

 

Step#2: initialize the encoder

/*

    Initilaize encoder by using base parameters.

  */

virtual int Initialize (const SEncParamBase* pParam) = 0;

/*

Initilaize encoder by using extension parameters. If the user needs to set the more details, refer to use this interface.

  */

virtual int InitializeExt (const SEncParamExt* pParam) = 0;

 

/*

   Get the default extension parameters . some time the user doesn’t care about all of the parameters. So he can get use the interface to get the default parameter, then updates these parameters he cares.

  */

virtual int GetDefaultParams (SEncParamExt* pParam) = 0;

 

virtual int Unintialize() = 0;

Step#3: invoker the encoding

/*

 * return: 0 - success; otherwise - failed;

 */

virtual int EncodeFrame(const SSourcePicture* kpSrcPic, SFrameBSInfo* pBsInfo) = 0;

 

SSourcePicture:

Format 

Parameter Name

Meaning/Constraint

int

iColorFormat

the input image color space format, currently only supports videoFormatI420

int

iStride[4]

The stride of picture buffer 

unsigned char

pData[4]

Pointer to the source data  

int

iPicWidth

width of picture in luminance samples

int

iPicHeight

height of picture in luminance samples

Long long

uiTimeStamp

Time stamp of the frame.

 

// kpSrc = the pointer to the source luminance plane

// chrominance data:

// CbData = kpSrc + m_iMaxPicWidth * m_iMaxPicHeight;

// CrData = CbData + (m_iMaxPicWidth * m_iMaxPicHeight)/4;

//the application calling this interface needs to ensure the data validation between the location of [kpSrc, kpSrc+framesize-1]

 

Step#4: control the encoding

The upper layer application should ensure threading safety between calling these control interfaces and calling the encoding. 

 

/*

  * return: 0 - success; otherwise - failed;

  */

virtual int PauseFrame(const SSourcePicture* kpSrcPic, SFrameBSInfo* pBsInfo) = 0;

/*

 * return: 0 - success; otherwise - failed;

 */

virtual int ForceIntraFrame(bool bIDR) = 0;

/***********************************************************************

 * InDataFormat, IDRInterval, SVC Encode Param, Frame Rate, Bitrate,..

**************************** ******************************************/

/*

 * return: CM_RETURN: 0 - success; otherwise - failed;

 */

virtual int SetOption(ENCODER_OPTION eOptionId, void* pOption) = 0;

virtual int GetOption(ENCODER_OPTION eOptionId, void* pOption) = 0;

 

 


Encoder Option List:

 

int CWelsH264SVCEncoder::SetOption(ENCODER_OPTION eOptionId, void* pOption)

Option ID

Input Format

Meaning/Constraint

ENCODER_OPTION_SVC_ENCODE_PARAM_BASE

Structure of Base Param

 

ENCODER_OPTION_SVC_ENCODE_PARAM_EXT

Structure of Extension Param

 

ENCODER_OPTION_IDR_INTERVAL

int

IDR period,

0/-1 means no Intra period (only the first frame)

>0 means the desired IDR period, must be multiple of (2^temporal_layer)

ENCODER_OPTION_FRAME_RATE

float

Maximal input frame rate, current supported range: 

MAX_FRAME_RATE = 30

MIN_FRAME_RATE = 1

ENCODER_OPTION_BITRATE

int

 

ENCODER_OPTION_MAX_BITRATE

int

 

ENCODER_PADDING_PADDING

int

0:disable padding;1:padding

ENCODER_LTR_RECOVERY_REQUEST

Structure of SLTRRecoverRequest

 

ENCODER_LTR_MARKING_FEEDBACK

Structure of SLTRMarkingFeedback

 

ENCOCER_LTR_MARKING_PERIOD

Unsigned int

 

ENCODER_OPTION_LTR

Unsigned int

0:not enable LTR;>0 enable LTR; 

LTR number is fixed to be 2 in current encoder

ENCODER_OPTION_ENABLE_PREFIX_NAL_ADDING

Bool

false:not use Prefix NAL; true: use Prefix NAL

ENCODER_OPTION_ENABLE_SPS_PPS_ID_ADDITION

Bool

false:not adjust ID in SPS/PPS; true: adjust ID in SPS/PPS

ENCODER_OPTION_CURRENT_PATH

string

 

ENCODER_OPTION_DUMP_FILE

Structure of SDumpLayer

Dump layer reconstruct frame to a specified file

ENCODER_OPTION_TRACE_LEVEL

int

Output some info accoding to the trace level

 

 

 

 

 

 


Encoder Parameter List:

(Note: some parameters in mentioned structure are not explained because they are to be removed)

 

SEncParamBase:

Format 

Parameter Name

Meaning/Constraint

int

iUsageType

Currently two type applications are supported. 

0: camera video 

1: screen content

int

iInputCsp

color space of input sequence

currently only supports videoFormatI420

int

iPicWidth

width of picture in luminance samples (the maximum of all layers if multiple spatial layers presents)

int

iPicHeight

height of picture in luminance samples((the maximum of all layers if multiple spatial layers presents)

int

iTargetBitrate

target bitrate 

int

iRCMode

Rate control mode

float

fMaxFrameRate

maximal input frame rate

 

 

SEncParamExt:

Format 

Parameter Name

Meaning/Constraint

int

iUsageType

Currently two type applications are supported. 

0: camera video 

1: screen content

int

iInputCsp

color space of input sequence

currently only supports videoFormatI420

int

iPicWidth

width of picture in luminance samples (the maximum of all layers if multiple spatial layers presents)

int

iPicHeight

height of picture in luminance samples((the maximum of all layers if multiple spatial layers presents)

int

iTargetBitrate

target bitrate 

int

iRCMode

Rate control mode

float

fMaxFrameRate

maximal input frame rate

int

iTemporalLayerNum

temporal layer number, max temporal layer = 4

int

iSpatialLayerNum

spatial layer number, 

1<= iSpatialLayerNum <= MAX_SPATIAL_LAYER_NUM

MAX_SPATIAL_LAYER_NUM = 4

SSpatialLayerConfig 

sSpatialLayers[MAX_SPATIAL_LAYER_NUM];

 

int

iInputCsp

color space of input sequence

int

iTemporalLayerNum

temporal layer number, max temporal layer = 4

int

iSpatialLayerNum

spatial layer number, 

1<= iSpatialLayerNum <= MAX_SPATIAL_LAYER_NUM

MAX_SPATIAL_LAYER_NUM = 4

unsigned int

uiIntraPeriod

period of IDR frame

int

iNumRefFrame

The number of the reference frame

Unsigned int

uiFrameToBeCoded

The number of the frames to be encoded. the user doesn’t know the number or doesn’t care the number,can set 0xFFFFFFFF.

bool    

bEnableSpsPpsIdAddition

false:not adjust ID in SPS/PPS; true: adjust ID in SPS/PPS

bool    

bPrefixNalAddingCtrl

false:not use Prefix NAL; true: use Prefix NAL

bool

bEnableSSEI

false:not use SSEI; true: use SSEI

int

iPaddingFlag

0:disable padding;1:padding

int

iEntropyCodingModeFlag

0:CAVLC  1:CABAC. 

Currently only supports CAVLC.

bool

bEnableRc

False: don’t use rate control; true: use rate control

bool

bEnableFrameSKip

False: don’t skip frame even if VBV buffer overflow.

True: allow skipping frames to keep the bitrate within limits

int

iMaxBitrate

the maximum bitrate 

int

iMaxQp

the maximum QP encoder supports 

int

iMinQp

The minmum QP encoder supports

Unsigned int

uiMaxNalSize

The maximum NAL size.  This value should be not 0 for dynamic slice mode

bool     

bEnableLongTermReference;

0: on, 1: off

int

iLTRRefNum

The number of LTR(long term reference)

int

iLtrMarkPeriod

The LTR marked period that is used in feedback. 

Short 

iMultipleThreadIdc

# 0: auto(dynamic imp. internal encoder); 1: multiple threads imp. disabled; > 1: count number of threads;

Int

iLoopFilterDisableIdc

0: on, 1: off, 2: on except for slice boundaries

Int

iLoopFilterAlphaC0Offset

AlphaOffset: valid range [-6, 6], default 0

Int

iLoopFilterBetaOffset

BetaOffset: valid range [-6, 6], default 0

bool   

bEnableDenoise;

denoise control

bool    

bEnableBackgroundDetection

background detection control 

bool    

bEnableAdaptiveQuant

adaptive quantization control

bool

bEnableFrameCroppingFlag;

enable cropping source picture

int

bEnableSceneChangeDetect

Enable scene change detection 

 

SSpatialLayerConfig

Format 

Parameter Name

Meaning/Constraint

int

iVideoWidth

width of picture in luminance samples of a layer

int

iVideoHeight

height of picture in luminance samples of a layer

float

fFrameRate

frame rate for a layer

int

iSpatialBitrate

target bitrate for a spatial layer

int

iMaxSpatialBitrate

Maximum  bitrate for a spatial layer

EProfileIdc

uiProfileIdc

value of profile IDC (0 for auto-detection)

ELevelIdc

uiLevelIdc

value of level IDC (0 for auto-detection)

Int 

iDLayerQp

Each layer QP for fixed quant case

SSliceConfig

sSliceCfg

slicing configuration

 

sSliceCfg.uiSliceMode

0: SM_SINGLE_SLICE: SliceNum==1

1: SM_FIXEDSLCNUM_SLICE: according to SliceNum, Enabled dynamic slicing for multi-thread

2: SM_RASTER_SLICE: according to SlicesAssign, Need input of MB numbers each slice. In addition, if other constraint in SSliceArgument is presented, need to follow the constraints. Typically if MB num and slice size are both constrained, re-encoding may be involved.

3: SM_ROWMB_SLICE: according to PictureMBHeight, a row of mbs per slice 

4: SM_DYN_SLICE: according to SliceSize,  Dynamic slicing (have no idea about slice_nums until encoding current frame)

 

sSliceCfg. sSliceArgument uiSliceMbNum

Used in uiSliceMode=2

 

sSliceCfg. sSliceArgument uiSliceNum

Used in uiSliceMode=1

 

sSliceCfg. sSliceArgument uiSliceSizeConstraint

Used in uiSliceMode=4

 


Encoder Return Value: CM_RETURN 

Return value of parameter Initializtion: Initialize() and set option SetOption()

Value 

Parameter Name

Meaning/Constraint

0

cmResultSuccess

Successful initialized

1

cmInitParaError

Found error in input parameters

2

cmMachPerfIsBad

Not supported yet

3

cmUnkonwReason

Not supported yet

4

cmMallocMemeError

Input source picture is NULL

cmInitExpected

Encoder is not created correctly

 

 

Encoder Return Value: EVideoFrameType:

Return value of encode one frame: EncodeFrame()

Value 

Parameter Name

Meaning/Constraint

0

videoFrameTypeInvalid

Encoder not ready or parameters are invalidate

1

videoFrameTypeIDR

IDR frame in H.264 

2

videoFrameTypeI

I frame type

3

videoFrameTypeP

P frame type

4

videoFrameTypeSkip

Encoder decides to skip the frame, no bit stream will be ouputed

videoFrameTypeIPMixed

A frame where I and P slices are mixing, not supported yet

 


Decoder Usage:

Step#1: create and destroy the decoder

int  WelsCreateDecoder(ISVCDecoder** ppDecoder);

void WelsDestroyDecoder(ISVCDecoder* pDecoder);

 

Step#2: initialize the decoder

virtual long Initialize(const SDecodingParam* pParam) = 0;   

virtual long Unintialize() = 0;

Step#3: invoker the decoding

/***************************************************************************

    *       Description:

    *    Decompress one frame or slice, and output I420 decoded data.

    *

    *Input parameters:

    *        ParameterTYPE Description

    *        kpSrcconst unsigned char* the h264 stream to be decoded

    *      kiSrcLenconst int                   the length of h264 steam

    *       ppDst            unsigned char**       buffer pointer of decoded data (YUV)

    *      pDstInfo       SBufferInfo*information provided to API including width, height, etc

    *pStrideint*output stride

    *iWidthint&output width

    *iHeightint&output height

    *

    *return: if decode frame success return 0, otherwise corresponding error returned.

/***************************************************************************/

//the following API is for slice level decoding

virtual DECODING_STATE DecodeFrame2(

const unsigned char* kpSrc, 

const int kiSrcLen,

unsigned char** ppDst,

SBufferInfo* pDstInfo);

 

//the following API is for frame level decoding

Virtual DECODING_STATE DecodeFrame(

const unsigned char* kpSrc,

const int kiSrcLen,

unsigned char** ppDst,

int* pStride,

int& iWidth,

int& iHeight );

//Note: DecodeFrameEx() is not used.

//Note: for slice level DecodeFrame2() (4 parameters input), whatever the function return value is, the outputted data of I420 format will only be available when pDstInfo->iBufferStatus == 1,. (e.g., in multi-slice cases, only when the whole picture is completely reconstructed, this variable would be set as 1.)  

Step#4: control the decoding

virtual int SetOption(DECODER_OPTION eOptionId, void* pOption) = 0;

virtual int GetOption(DECODER_OPTION eOptionId, void* pOption) = 0;


Decoder Option List:

 

Option ID

Input Format

Meaning/Constraint

DECODER_OPTION_DATAFORMAT

int

color format, now supports 23 only (I420)

DECODER_OPTION_END_OF_STREAM

bool

end of stream flag

DECODER_OPTION_VCL_NAL

bool

feedback whether or not have VCL NAL in current AU for application layer

DECODER_OPTION_TEMPORAL_ID

int

if have VCL NAL in current AU, then feedback the temporal ID

DECODER_OPTION_FRAME_NUM

int

Indicate frame_num

DECODER_OPTION_IDR_PIC_ID

int

Indicate current IDR_ID

DECODER_OPTION_LTR_MARKING_FLAG

bool

read only, indicating if LTR_marking SE flag is used in current AU

DECODER_OPTION_LTR_MARKED_FRAME_NUM

int

Read only, indicating the frame_num of current AU marked as LTR

DECODER_OPTION_ERROR_CON_IDC

int

Indicate error concealment method

0: disable

1: frame_copy

2: slice_copy (default)

 

 

 

 

 

 


Decoder Parameter List:

(Note: some parameters in mentioned structure are not explained because they are to be removed)

 

SDecodingParam: (Note: some of the members may not be used for now.)

Format 

Parameter Name

Meaning/Constraint

char*

pFileNameRestructed

File name of restructed frame used for PSNR calculation based debug;

int

iOutputColorFormat

color space format to be outputed

unsigned int

uiCpuLoad

CPU load

unsigned char

uiTargetDqLayer

target dq layer number 

unsigned char

uiEcActiveFlag

Whether active error concealment feature in decoder

SVideoProperty

sVideoProperty

Video stream property

 

SVideoProperty

Format 

Parameter Name

Meaning/Constraint

unsigned int

size

size of structure

VIDEO_BITSTREAM_TYPE

eVideoBsType

Video stream type (AVC/SVC)

 

SBufferInfo: 

Format 

Parameter Name

Meaning/Constraint

int

iBufferStatus

0: data not ready, 1: data ready

union UsrData

 

Output buffer info, see following tables

union UsrData: 

Format 

Parameter Name

Meaning/Constraint

SSysMEMBuffer

sSysMEMBuffer

output with memory, see following tables

SSysMEMBuffer

Format 

Parameter Name

Meaning/Constraint

int

iWidth

width of decoded pic

int

iHeight

height of decoded pic

int

iFormat

type is “EVideoFormatType”, see codec_def.h

int

iStride[2]

stride

 

Decoder Usage Example:

 

A dummy process for using the decoder could be: (for static library)

1. ISVCDecoder *pSvcDecoder;  //declare a decoder

    unsigned char *pBuf = …; //input: encoded bitstream start position; should include start code prefix

    int iSize = …; //input: encoded bitsteam length; should include the size of start code prefix

    unsigned char *pData[3] = …; //output: [0~2] for Y,U,V buffer

    SBufferInfo sDstBufInfo; //in-out: declare the output buffer info

    memset(&sDstBufInfo, 0, sizeof(SBufferInfo));

2. CreateDecoder(pSvcDecoder); //create a decoder

3. SDecodingParam sDecParam = {0}; //declare required param

    sDecParam.sVideoProperty.eVideoBsType = VIDEO_BITSTREAM_AVC;

4. Initialize(&sDecParam); //initialize the param and decoder context, allocate memory

5. DecodeFrame2(pBuf, iSize, pData, &sDstBufInfo); //do actual decoding for slice/frame level; this can be done in a loop until data ends

//if (sDstBufInfo.iBufferStatus==1), pData can be used for render.

6. Uninitialize(); //Uninitialize the decoder and memory free.

7. DestroyDecoder(); //Destroy the decoder

 


README.md文档

OpenH264
========
OpenH264 is a codec library which supports H.264 encoding and decoding. It is suitable for use in real time applications such as WebRTC. See http://www.openh264.org/ for more details.


Encoder Features
----------------
- Constrained Baseline Profile up to Level 5.2 (4096x2304)
- Arbitrary resolution, support cropping
- Rate control with adaptive quantization, or constant quantization
- Slice options: 1 slice per frame, N slices per frame, N macroblocks per slice, or N bytes per slice
- Multiple threads automatically used for multiple slices
- Temporal scalability up to 4 layers in a dyadic hierarchy
- Spatial simulcast up to 4 resolutions from a single input
- Long Term Reference (LTR) frames
- Memory Management Control Operation (MMCO)
- Reference picture list modification
- Single reference frame for inter prediction
- Multiple reference frames when using LTR and/or 3-4 temporal layers
- Periodic and on-demand Instantaneous Decoder Refresh (IDR) frame insertion
- Dynamic changes to bit rate, frame rate, and resolution
- Annex B byte stream output
- YUV 4:2:0 planar input


Decoder Features
----------------
- Constrained Baseline Profile up to Level 5.2 (4096x2304)
- Arbitrary resolution, not constrained to multiples of 16x16
- Single thread for all slices
- Long Term Reference (LTR) frames
- Memory Management Control Operation (MMCO)
- Reference picture list modification
- Multiple reference frames when specified in Sequence Parameter Set (SPS)
- Annex B byte stream input
- YUV 4:2:0 planar output
- Decoder output timing conformance
- Error concealment support with slice copy as default method


OS Support
----------
- Windows 64-bit and 32-bit
- Mac OS X 64-bit and 32-bit
- Linux 64-bit and 32-bit
- Android 32-bit
- iOS 64-bit and 32-bit (not fully tested)


Processor Support
-----------------
- Intel x86 optionally with MMX/SSE (no AVX yet, help is welcome)
- ARMv7 optionally with NEON
- Any architecture using C/C++ fallback functions


Building the Library
--------------------
NASM needed to be installed for assembly code: workable version 2.07 or above, nasm can downloaded from http://www.nasm.us/


To build the arm assembly for Windows Phone, gas-preprocessor is required. It can be downloaded from git://git.libav.org/gas-preprocessor.git


For Android Builds
------------------
To build for android platform, You need to install android sdk and ndk. You also need to export **ANDROID_SDK**/tools to PATH. On Linux, this can be done by


'export PATH=**ANDROID_SDK**/tools:$PATH'


The codec and demo can be built by


'make OS=android NDKROOT=**ANDROID_NDK** TARGET= **ANDROID_TARGET**'


Valid **ANDROID_TARGET** can be found in **ANDROID_SDK**/platforms, such as android-12.
You can also set ARCH, NDKLEVEL, GCCVERSION according to your device and NDK version.
ARCH specifies the architecture of android device. Currently only arm and x86 are supported, the default is arm.
NDKLEVEL specifies android api level, the api level can be 12-19, the default is 12.
GCCVERSION specifies which gcc in NDK is used, the default is 4.8.


By default these commands build for the armeabi-v7a ABI. To build for the other android
ABIs, add "ARCH=mips" or "ARCH=x86". To build for the older armeabi ABI (which has
armv5te as baseline), add "APP_ABI=armeabi" (ARCH=arm is implicit).


For iOS Builds
--------------
You can build the libraries and demo applications using xcode project files
located in codec/build/iOS/dec and codec/build/iOS/enc.


You can also build the libraries (but not the demo applications) using the
make based build system from the command line. Build with


'make OS=ios ARCH=**ARCH**'


Valid values for **ARCH** are the normal iOS architecture names such as
armv7, armv7s, arm64, and i386 and x86_64 for the simulator. Additionally,
one might need to add 'SDK=X.Y' to the make command line in case the default
SDK version isn't available. Another settable iOS specific parameter
is SDK_MIN, specifying the minimum deployment target for the built library.
For other details on building using make on the command line, see
'For All Platforms' below.


For Windows Builds
------------------


Our Windows builds use MinGW which can be found here - http://www.mingw.org/


To build with gcc, add the MinGW bin directory (e.g. /c/MinGW/bin) to your path and follow the 'For All Platforms' instructions below.


To build with Visual Studio you will need to set up your path to run cl.exe.  The easiest way is to start MSYS from a developer command line session - http://msdn.microsoft.com/en-us/library/ms229859(v=vs.110).aspx  If you need to do it by hand here is an example from a Windows 64bit install of VS2012:


export PATH="$PATH:/c/Program Files (x86)/Microsoft Visual Studio 11.0/VC/bin:/c/Program Files (x86)/Microsoft Visual Studio 11.0/Common7/IDE"


You will also need to set your INCLUDE and LIB paths to point to your VS and SDK installs.  Something like this, again from Win64 with VS2012 (note the use of Windows-style paths here).


export INCLUDE="C:\Program Files (x86)\Microsoft Visual Studio 11.0\VC\include;C:\Program Files (x86)\Windows Kits\8.0\Include\um;C:\Program Files (x86)\Windows Kits\8.0\Include\shared"
export LIB="C:\Program Files (x86)\Windows Kits\8.0\Lib\Win8\um\x86;C:\Program Files (x86)\Microsoft Visual Studio 11.0\VC\lib"


Then add 'OS=msvc' to the make line of the 'For All Platforms' instructions.


For All Platforms
-------------------
From the main project directory:
'make' for automatically detecting 32/64bit and building accordingly
'make ENABLE64BIT=No' for 32bit builds
'make ENABLE64BIT=Yes' for 64bit builds
'make V=No' for a silent build (not showing the actual compiler commands)


The command line programs h264enc and h264dec will appear in the main project directory.


A shell script to run the command-line apps is in testbin/CmdLineExample.sh


Usage information can be found in testbin/CmdLineReadMe


Using the Source
----------------
codec - encoder, decoder, console (test app), build (makefile, vcproj)
build - scripts for Makefile build system.
test - GTest unittest files.
testbin - autobuild scripts, test app config files
res - yuv and bitstream test files


Known Issues
------------
See the issue tracker on https://github.com/cisco/openh264/issues
- Encoder errors when resolution exceeds 3840x2160
- Encoder errors when compressed frame size exceeds half uncompressed size
- Encoder does not support QP < 10 encoding
- Encoder does not support slice number > 35 encoding
- The result of float-point calculation in rate control will be affected by preciseness of double-typed variable on different platform
- Decoder errors when compressed frame size exceeds 1MB
- Encoder RC requires frame skipping to be enabled to hit the target bitrate,
  if frame skipping is disabled the target bitrate may be exceeded


License
-------
BSD, see LICENSE file for details.

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