Created
June 29, 2022 08:58
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read mp4 video using openh264 + minimp4.h
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| #include <cassert> | |
| #include <cstdint> | |
| #include <cstring> | |
| #include <iostream> | |
| #include <fstream> | |
| #include <vector> | |
| #define MINIMP4_IMPLEMENTATION | |
| #include "minimp4.h" | |
| #include "../codec/api/wels/codec_api.h" | |
| size_t g_size = 0; | |
| int read_cb(int64_t off, void* buf, size_t size, void* ptr) { | |
| std::ifstream* f = (std::ifstream*) ptr; | |
| size_t n = g_size - off - size; | |
| if (size < n) n = size; | |
| f->seekg(off); | |
| assert(*f); | |
| f->read((char*) buf, n); | |
| assert(*f); | |
| return 0; | |
| } | |
| int main() { | |
| std::ifstream f("hello.mp4", std::ifstream::binary | std::ifstream::ate); | |
| g_size = f.tellg(); | |
| assert(f); | |
| // decoder init | |
| ISVCDecoder* dec; | |
| WelsCreateDecoder(&dec); | |
| SDecodingParam dparam = {}; | |
| dparam.sVideoProperty.eVideoBsType = VIDEO_BITSTREAM_AVC; | |
| dparam.sVideoProperty.eVideoBsType = VIDEO_BITSTREAM_DEFAULT; | |
| dparam.eEcActiveIdc = ERROR_CON_SLICE_COPY; | |
| dec->Initialize(&dparam); | |
| int level = WELS_LOG_DEBUG; | |
| dec->SetOption(DECODER_OPTION_TRACE_LEVEL, &level); | |
| uint8_t* yuv[3] = {0}; | |
| SBufferInfo frame = {}; | |
| // demux | |
| MP4D_demux_t dem = {}; | |
| MP4D_open(&dem, read_cb, &f, g_size); | |
| std::vector<uint8_t> temp; | |
| for (int ti = 0; ti < dem.track_count; ++ti) { | |
| const auto& t = dem.track[ti]; | |
| if (t.handler_type == MP4D_HANDLER_TYPE_VIDE) { | |
| for (size_t si = 0;; ++si) { | |
| int sz; | |
| auto sps = (uint8_t*) MP4D_read_sps(&dem, ti, si, &sz); | |
| if (!sps) break; | |
| std::cout << "sps#" << si << std::endl; | |
| temp.resize(sz+4); | |
| temp[0] = 0; | |
| temp[1] = 0; | |
| temp[2] = 0; | |
| temp[3] = 1; | |
| std::memcpy(&temp[4], sps, sz); | |
| auto ret = dec->DecodeFrameNoDelay(temp.data(), temp.size(), yuv, &frame); | |
| std::cout << " ret: " << ret << std::endl; | |
| } | |
| for (size_t pi = 0;; ++pi) { | |
| int sz; | |
| auto pps = (uint8_t*) MP4D_read_pps(&dem, ti, pi, &sz); | |
| if (!pps) break; | |
| std::cout << "pps#" << pi << std::endl; | |
| temp.resize(sz+4); | |
| temp[0] = 0; | |
| temp[1] = 0; | |
| temp[2] = 0; | |
| temp[3] = 1; | |
| std::memcpy(&temp[4], pps, sz); | |
| auto ret = dec->DecodeFrameNoDelay(temp.data(), temp.size(), yuv, &frame); | |
| std::cout << " ret: " << ret << std::endl; | |
| } | |
| for (size_t si = 0; si < t.sample_count; ++si) { | |
| unsigned fsz, time, dur; | |
| const auto off = MP4D_frame_offset(&dem, ti, si, &fsz, &time, &dur); | |
| std::cout << "frame#" << si << std::endl; | |
| std::cout << " off: " << off << std::endl; | |
| f.seekg(off); | |
| assert(f); | |
| temp.resize(fsz); | |
| f.read((char*) temp.data(), fsz); | |
| assert(f); | |
| for (size_t i = 0; i < temp.size();) { | |
| uint32_t sz = (temp[i] << 24) | (temp[i+1] << 16) | (temp[i+2] << 8) | temp[i+3]; | |
| sz += 4; | |
| temp[0] = 0; | |
| temp[1] = 0; | |
| temp[2] = 0; | |
| temp[3] = 1; | |
| auto ret = dec->DecodeFrameNoDelay(&temp[i], sz, yuv, &frame); | |
| std::cout << " result: " << ret << std::endl; | |
| i += sz; | |
| } | |
| } | |
| } else { | |
| assert(false); | |
| } | |
| } | |
| MP4D_close(&dem); | |
| dec->Uninitialize(); | |
| WelsDestroyDecoder(dec); | |
| } |
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