Waehere o ngā mōhiohio ororongo

mau e taea te tahuri tetahi tukanga ki puka mamati. Ko te kupu, whakahekea whakawaehere o ngā mōhiohio oro mā rorohiko i roto e whai ake:

- tuhia wiri rangi pūrere tairongo;

- mahi ana faafariuraa ki te nāianei hiko, ai te auau (tīwera) rerekē fakatatau;

- tango te nāianei hua ko, i.e. reira he tona tīpako (i ētahi wā mea e mau whakawaehere mōhiohio audio rua).

Ko te tairitenga rere hiko taketake audio hua te pai, te teitei te auau o te tauira i te tīpako me te hohonu Tapa.

I roto i te mau parau te tahi atu, whakawaehere o te mōhiohio oro - ko te tukanga maheni o te faafariuraa maha tohu tairitenga ki te mamati, te tikanga mo te tukatuka atu ki te pūrere e tika ana. Kia whai whakaaro ano tatou nga kaupae me ngā tikanga o whakamamati tangi.

Discretization o te anga wā - ko te pūtake mō te whakamamati. E ai Kotel'nikova ture tauwehe, te taea te whakamamatitia orotahi tohu hiko mā te tai'oraa i te tetahi taahiraa o te raupapa tonu o ngā uara o tona kaha tīwera. kia te auau o taua pānuitanga i te iti rawa rua te auau rohe o te tohu matua. Ki te kia kawea e tika ana, whakamamati orotahi "waehere pūtake" ki te auau whakahaere o 0-20 kHz tīpako i kore iti iho i te 40 mano. Times ia te rua (40 kHz). E pā ana tauira ki te maha o inenga ia te rua puna tairitenga tohu (tīpako, te auau tauira). Ki te whakanui ake i piki tauira te kounga e kore anake, engari ano hoki te rōrahi o te awa raraunga hua.

Hoki, kia kia whakamana oro mōhiohio waehere i roto i te tahi atu mau rave'a. Ka rite ki, hei tauira, mā te whakamamati te quantizer nonuniform, i ētahi wā ka karangatia e pākoki. A, no te whakamahi i te whānuitanga tīwera katoa herenga wehea ki ngā wāhanga ki te uara tiketike, me te iti. Ētahi atu whakawaehere mōhiohio audio puta na roto i te faaohiparaa i nui o ngā taumata quantization i roto i ngā wāhi ki te uara tīwera iti (me te hurihia). Kia mōhio, Heoi, e noho tonu te tapeke maha o ngā taumata te taua rite i roto i te tikanga quantization kākahu (PCM).

whakatinana He huarahi katoa rerekē i roto i te tikanga whakawaehere kē. Kei te karanga a te reira "Pulse Pārōnaki Waehere Kōwaetanga» (DPCM). Ki te tikanga taua e kore e waiho i raro ki te quantization o te kaha tīwera o te tohu tika, me tona uara whanaunga. Ka rite ki te hua ka taea ki te whakatutuki whakaiti o te rōrahi nohoia e te raraunga, mai whakahaeretia te huarahi te matapae muri o te tauira tohu taketake.

Te mōhiohio waehere me te tukatuka ororongo whakaahuatia i roto i tenei pepa tā te raveraa i te faafariuraa "tairitenga-ki-mamati". whakamana ana tēnei tukanga te whakamahi i te ADC (tairitenga-ki-mamati pūtahuri). Ki tenei mahi, anga ia pūrere rangatira rorohiko rā rite rawa ki te kāri tangi (i roto i tenei take i reira ko te tukanga whakamuri - te fariiraa i te tohu tairitenga i te awa mamati).

He mahi ADC e whai ake:

- iti hōkaiipurangi auau. Mā te tātari, e hatepea atu nga wāhanga tohu, te auau o nei - neke atu i te hawhe te auau tīpako (te take whakaahuatia mua).

- Tīpakonga o nga uara tīwera i wā auau. Ko te hua tairitenga tohu e māngai e te raupapa o nga paraire kotahi o rerekē kaha (discretization).

- riro rahinga Whakakapinga paraire ratou uara tata i te huinga pūmau (quantization).

- Tahuri ia uara quantized o te maha herenga o ngā taumata quantization (ia uara - tona tau rangatū). Ko te wā whakamutunga o te whakarorohikotanga tenei.