{"id":232,"date":"2022-09-15T11:26:08","date_gmt":"2022-09-15T03:26:08","guid":{"rendered":"https:\/\/www.346pro.club\/?p=232"},"modified":"2022-09-15T11:26:08","modified_gmt":"2022-09-15T03:26:08","slug":"%e5%9f%ba%e4%ba%8eeigen%e7%9a%84libwav%e8%a7%a3%e7%a0%81%e5%ba%93","status":"publish","type":"post","link":"https:\/\/www.346pro.club\/?p=232","title":{"rendered":"\u57fa\u4e8eeigen\u7684libwav\u89e3\u7801\u5e93"},"content":{"rendered":"\n

EmiyaEngine\u2014\u2014\u4e00\u4e2a\u6d4b\u8bd5\u7248\u7684\u7384\u5b66\u5bb6\u751f\u6210\u5668<\/a><\/p><\/blockquote>\n\n\n\n

\u8981\u89e3\u7801\u4e00\u4e2awav\uff0c\u9996\u5148\u6211\u4eec\u8981\u4e86\u89e3wav\u6587\u4ef6\u7684\u7ed3\u6784\u3002<\/p>\n\n\n\n

wav\u6587\u4ef6\u5206\u4e3a\u5934\u6807\u8bc6\u548c\u6570\u636e\u6d41\u4e24\u90e8\u5206\uff0c\u5934\u6807\u8bc6\u90e8\u5206\u51b3\u5b9a\u4e86wav\u7684\u4e00\u4e9b\u6587\u4ef6\u53c2\u6570\uff0c\u800c\u6570\u636e\u6d41\u90e8\u5206\u5219\u662f\u771f\u6b63\u7684\u97f3\u9891\u6570\u636e\u3002<\/p>\n\n\n\n

\u56e0\u6b64\uff0c\u6211\u4eec\u5148\u5b9a\u4e49\u4e00\u4e2a\u7ed3\u6784\u4f53\uff0c\u7528\u4e8e\u50a8\u5b58wav\u7ed3\u6784\u4fe1\u606f<\/p>\n\n\n\n

struct wav_reader\n{\n    std::vector<unsigned char> wav;\n    uint32_t data_pos{};\n    uint32_t data_length{};\n    uint32_t data_left{};\n\n    uint32_t format{};\n    uint32_t sample_rate{};\n    int bits_per_sample{};\n    int channels{};\n    uint32_t byte_rate{};\n    int block_align{};\n\n    int streamed{};\n};<\/pre>\n\n\n\n
\u7136\u540e\u6b63\u5e38\u8bfb\u53d6\u6587\u4ef6\uff0c\u6ce8\u610f\uff0c\u8bfb\u53d6\u4e8c\u8fdb\u5236\u6587\u4ef6\u7684\u65f6\u5019\uff0c\u5b83\u7684\u6570\u636e\u7c7b\u578b\u662funsigned char<\/p>\n\n\n\n
std::basic_ifstream<unsigned char> fin(file_path, std::ios::in | std::ios::binary);\nif (!fin.is_open())\n    throw std::exception(\"Error opening file\");\n\nfin.seekg(0, std::ios::end);\nconst auto sizes = fin.tellg();\nwr->wav.resize(sizes);\nfin.seekg(0);\nfin.read(wr->wav.data(), sizes);\nfin.close();<\/pre>\n\n\n\n
\u8bfb\u53d6\u51fa\u6765\u7684\u6587\u4ef6\uff0c\u5982\u679c\u4e3awav\u683c\u5f0f\uff0c\u90a3\u6700\u5f00\u59cb\u56db\u4e2a\u4f4d\u7684\u5b57\u7b26\u4e32\uff0c\u4e00\u5b9a\u662f\"RIFF\"\u3002<\/p>\n\n\n\n
\u4e4b\u540e\u7684\u56db\u4e2a\u4f4d\u5b57\u7b26\u4e32\uff0c\u5b83\u4ee3\u8868\u7684\u662f\u8fd9\u7ec4\u97f3\u9891\u6587\u4ef6\u7684\u6709\u6548\u957f\u5ea6\uff0c\u9700\u8981\u75284\u4f4d\u7684unsigned char\u8f6c\u6362\u523032\u4f4d\u7684uint32\uff0c\u4e5f\u5c31\u662funsigned int\u3002<\/p>\n\n\n\n
\u4e4b\u540e\u7684\u56db\u4f4d\u6709\u6548\u5b57\u7b26\u4e32\uff0c\u662f\u4e00\u4e2a\u4ee3\u8868wav\u6587\u4ef6\u7684\"WAVE\"\u3002<\/p>\n\n\n\n
\u4e4b\u540e\u8fd8\u662f\u4e00\u4e324\u4f4d\u6709\u6548\u5b57\u7b26\u4e32\uff0c\u63a5\u7740\u662f\u4e00\u4e2a32\u4f4d\u7684uint32\uff0c\u4ee3\u8868\u5b50\u4e32\u7684\u6709\u6548\u957f\u5ea6\uff0c\u4e5f\u5c31\u662f\u5305\u542b\u5728\u540e\u9762\u7684wav\u4fe1\u606f\u7684\u6709\u6548\u957f\u5ea6\u3002<\/p>\n\n\n\n
\u4e4b\u540e\u5c31\u662fwav\u7684\u5934\u6587\u4ef6\u6807\u8bc6\uff0c\u5176\u4e2d\u4e00\u90e8\u5206\u662f32\u4f4d\u7684uint32\uff0c\u4e00\u90e8\u5206\u662f16\u4f4d\u7684uint16\uff0c\u4e5f\u5c31\u662funsigned short\uff0c\u76f4\u63a5\u4e0a\u4ee3\u7801<\/p>\n\n\n\n
wr->format = read_int16(wr, ptrs);\nwr->channels = read_int16(wr, ptrs);\nwr->sample_rate = read_int32(wr, ptrs);\nwr->byte_rate = read_int32(wr, ptrs);\nwr->block_align = read_int16(wr, ptrs);\nwr->bits_per_sample = read_int16(wr, ptrs);<\/pre>\n\n\n\n
\u6309\u7167\u987a\u5e8f\u8bfb\u53d6\uff0c\u5c31\u53ef\u4ee5\u83b7\u53d6\u5230\u6574\u4e2awav\u6587\u4ef6\u7684\u4fe1\u606f\uff0c\u5305\u62ec\u683c\u5f0f\uff0c\u901a\u9053\u6570\uff0c\u91c7\u6837\u7387\u7b49\u3002<\/p>\n\n\n\n
\u4e4b\u540e\u7ee7\u7eed\u8bfb\u53d6\uff0c\u5e94\u8be5\u662f\u4e00\u4e2a\u56db\u4f4d\u5b57\u7b26\u4e32\"LIST\"\uff0c\u4ee5\u53ca\u4e4b\u540e4\u4f4d\u7684\u4e00\u4e2aint32\u6709\u6548\u957f\u5ea6\uff0c\u8fd9\u4e00\u8282\u53ef\u4ee5\u6574\u4f53\u8df3\u8fc7\u3002<\/p>\n\n\n\n
\u5728\u4e4b\u540e\uff0c\u5c31\u662f\u56db\u4f4d\u5b57\u7b26\u4e32\"data\"\uff0c\u987e\u540d\u601d\u4e49\uff0c\u8fd9\u662f\u6574\u4e2a\u97f3\u9891\u6d41\u7684\u6570\u636e\u6a21\u5757\uff0c\u4ee5\u53ca\u4e00\u4e2a4\u4f4d\u7684int32\uff0c\u4ee3\u8868\u4e86\u6570\u636e\u6d41\u7684\u957f\u5ea6\uff0c\u6211\u4eec\u628a\u8fd9\u6bb5\u6570\u636e\u6d41\u6574\u4e2a\u653e\u8fdb\u4e00\u4e2aunsigned char\u7684\u6570\u7ec4\u91cc\u9762\uff0c\u5e76\u4e14\u8bb0\u5f55\u4e0b\u5b83\u5728\u6587\u4ef6\u6d41\u4e2d\u7684\u8d77\u70b9\uff1b\u8fd9\u6837\uff0c\u4e00\u4e2aunsigned char\u7684wav\u6587\u4ef6\u5c31\u5e94\u8be5\u89e3\u6790\u5b8c\u6bd5\u4e86<\/p>\n\n\n\n
wr->data_pos = ptrs;\nwr->data_length = sublength;\nwr->data_left = wr->data_length;<\/pre>\n\n\n\n
\u4f46\u662f\u89e3\u6790\u5b8c\u4e86\u6570\u636e\u6d41\u53ef\u80fd\u8fd8\u4e0d\u591f\uff0c\u8fd8\u5f97\u628aunsigned char\u7684\u6570\u636e\uff0c\u8f6c\u6362\u6210eigen\u7684\u6570\u503c\u6570\u636e\uff0c\u6240\u4ee5\u6211\u4eec\u9700\u8981\u628a\u8bfb\u53d6\u5230\u7684\u6587\u4ef6\u6d41\u6570\u636e\u590d\u5236\u51fa\u6765\uff0c\u76f4\u63a5\u8fdb\u884c\u5185\u5b58\u8f6c\u6362\u800c\u4e0d\u662f\u5f3a\u8f6c\uff0c\u6765\u5c06\u5176\u8f6c\u6362\u6210short\u6570\u636e\u6d41<\/p>\n\n\n\n
const auto samples = wr->data_length * 8 \/ wr->bits_per_sample;\nstd::vector<int16_t> tmp(samples);\n\nconst std::vector<unsigned char>::const_iterator first1 = wr->wav.begin() + wr->data_pos;\nconst std::vector<unsigned char>::const_iterator last1 = wr->wav.begin() + wr->data_pos + wr->data_length;\nconst std::vector data(first1, last1);\nmemcpy(tmp.data(), data.data(), wr->data_length);<\/pre>\n\n\n\n
\u4e4b\u540e\u5c06int\u6570\u636e\u91cf\uff0c\u8f6c\u6362\u5230eigen\u7684matrix\u6570\u636e\u6d41\u5c31\u884c\u4e86\u3002<\/p>\n\n\n\n
std::vector<double> x(samples);\nstd::ranges::transform(tmp, x.begin(), [](const int16_t a) { return static_cast<double>(a) \/ 32767.; });\n\nreturn Eigen::Map<Matrixd>(x.data(), samples \/ wr->channels, wr->channels);<\/pre>\n","protected":false},"excerpt":{"rendered":"
EmiyaEngine\u2014\u2014\u4e00\u4e2a\u6d4b\u8bd5\u7248\u7684\u7384\u5b66\u5bb6\u751f\u6210\u5668…<\/p>\n
Continue reading\u57fa\u4e8eeigen\u7684libwav\u89e3\u7801\u5e93<\/span><\/a><\/div>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[],"class_list":["post-232","post","type-post","status-publish","format-standard","hentry","category-technology","entry"],"_links":{"self":[{"href":"https:\/\/www.346pro.club\/index.php?rest_route=\/wp\/v2\/posts\/232","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.346pro.club\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.346pro.club\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.346pro.club\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.346pro.club\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=232"}],"version-history":[{"count":0,"href":"https:\/\/www.346pro.club\/index.php?rest_route=\/wp\/v2\/posts\/232\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.346pro.club\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=232"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.346pro.club\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=232"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.346pro.club\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=232"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}