codekingpro/portable-devtools

1/*
2* Copyright 2017-2024 NVIDIA Corporation.  All rights reserved.
3*
4* Please refer to the NVIDIA end user license agreement (EULA) associated
5* with this source code for terms and conditions that govern your use of
6* this software. Any use, reproduction, disclosure, or distribution of
7* this software and related documentation outside the terms of the EULA
8* is strictly prohibited.
9*
10*/
11
12//---------------------------------------------------------------------------
13//! \file AppDecLowLatency.cpp
14//! \brief Source file for AppDecLowLatency sample
15//!
16//! This sample application demonstrates low latency decoding feature.
17//! This feature helps to get output frame as soon as it is decoded without any delay.
18//! The feature will work for streams having I and P frames only.
19//---------------------------------------------------------------------------
20
21#include <vector>
22#include <cuda.h>
23#include "NvDecoder/NvDecoder.h"
24#include "../Utils/NvCodecUtils.h"
25#include "../Utils/FFmpegDemuxer.h"
26#include "../Common/AppDecUtils.h"
27
28simplelogger::Logger *logger = simplelogger::LoggerFactory::CreateConsoleLogger();
29
30int main(int argc, char *argv[]) 
31{
32    char szInFilePath[256] = "", szOutFilePath[256] = "out.yuv";
33    int iGpu = 0;
34    bool bVerbose = false;
35    // With zero latency flag enabled, HandlePictureDisplay() callback happens immediately for 
36    // the All-Intra/IPPP streams
37    bool force_zero_latency = false;
38    try
39    {
40        ParseCommandLine(argc, argv, szInFilePath, szOutFilePath, iGpu, &bVerbose, NULL, &force_zero_latency);
41        CheckInputFile(szInFilePath);
42
43        ck(cuInit(0));
44        int nGpu = 0;
45        ck(cuDeviceGetCount(&nGpu));
46        if (iGpu < 0 || iGpu >= nGpu)
47        {
48            std::ostringstream err;
49            err << "GPU ordinal out of range. Should be within [" << 0 << ", " << nGpu - 1 << "]" << std::endl;
50            throw std::invalid_argument(err.str());
51        }
52
53        CUcontext cuContext = NULL;
54        createCudaContext(&cuContext, iGpu, 0);
55
56        FFmpegDemuxer demuxer(szInFilePath);
57        // Here set bLowLatency=true in the constructor.
58        // Please don't use this flag except for low latency, it is harder to get 100% utilization of
59        // hardware decoder with this flag set.
60        NvDecoder dec(cuContext, false, FFmpeg2NvCodecId(demuxer.GetVideoCodec()), true, false, NULL, NULL, false, 0, 0, 1000, force_zero_latency);
61
62        int nFrame = 0;
63        uint8_t *pVideo = NULL;
64        int nVideoBytes = 0;
65        std::ofstream fpOut(szOutFilePath, std::ios::out | std::ios::binary);
66        if (!fpOut)
67        {
68            std::ostringstream err;
69            err << "Unable to open output file: " << szOutFilePath << std::endl;
70            throw std::invalid_argument(err.str());
71        }
72
73        int n = 0;
74        bool bOneInOneOut = true;
75        int nFrameReturned = 0;
76        int64_t timestamp = 0;
77        do {
78            demuxer.Demux(&pVideo, &nVideoBytes);
79            // Set flag CUVID_PKT_ENDOFPICTURE to signal that a complete packet has been sent to decode
80            nFrameReturned = dec.Decode(pVideo, nVideoBytes, CUVID_PKT_ENDOFPICTURE, n++);
81            if (!nFrame && nFrameReturned)
82                LOG(INFO) << dec.GetVideoInfo();
83
84            nFrame += nFrameReturned;
85            // For a stream without B-frames, "one in and one out" is expected, and nFrameReturned should be always 1 for each input packet
86            if (bVerbose)
87            {
88                std::cout << "Decode: nVideoBytes=" << nVideoBytes << ", nFrameReturned=" << nFrameReturned << ", total=" << nFrame << std::endl;
89            }
90            if (nVideoBytes && nFrameReturned != 1)
91            {
92                bOneInOneOut = false;
93            }
94            for (int i = 0; i < nFrameReturned; i++) 
95            {
96                fpOut.write(reinterpret_cast<char*>(dec.GetFrame(&timestamp)), dec.GetFrameSize());
97                if (bVerbose)
98                {
99                    std::cout << "Timestamp: " << timestamp << std::endl;
100                }
101            }
102        } while (nVideoBytes);
103
104        fpOut.close();
105        std::cout << "One packet in and one frame out: " << (bOneInOneOut ? "true" : "false") << std::endl;
106    }
107    catch(const std::exception& ex)
108    {
109        std::cout << ex.what();
110        exit(1);
111    }
112    return 0;
113}
114