- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄370406 > H.261 (Electronic Theatre Controls, Inc.) LINE TRANSMISSION OF NON-TELEPHONE SIGNALS PDF資料下載
參數(shù)資料
| 型號： | H.261 |
| 廠商： | Electronic Theatre Controls, Inc. |
| 英文描述： | LINE TRANSMISSION OF NON-TELEPHONE SIGNALS |
| 中文描述： | 線傳輸非電話信號 |
| 文件頁數(shù)： | 30/31頁 |
| 文件大?。?/td> | 123K |
| 代理商： | H.261 |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁當(dāng)前第30頁第31頁
Recommendation H.261 (03/93)
27
Several measurements should be made during the sequence length and the average period obtained. Several tests should be
made to ensure that a consistent average figure can be obtained for both encoder and decoder delay times.
Average results should be obtained for each combination of picture format and bit rate within the capability of the particular
codec design.
NOTE – Due to pre- and post-temporal processing it may be necessary to take a mid-level for establishing the transition of the
identification mark at points B and C.
A
C
B
T 1 5 0 2 4 8 0 9 0 d 1 0
V d e o
c o d e
V i d e o
d e c o d e
F G U R E C 1 H 2 6 1
M a s u n g p o n
FIGURE C.1/H.261...[
D10
] = 6CM
Annex D
Still image transmission
(This annex forms an integrat part of this Recommendation)
D.1
Introduction
This annex describes the procedure for transmitting still images within the framework of this Recommendation. This
procedure enables an H.261 video coder to transmit still images at four times the normal video resolution by temporarily
stopping the motion video. Administrations may use this optional procedure as a simple and inexpensive method to transmit
still images. However, Recommendation T.81 (JPEG) is preferred when the procedures for using T.81 within audiovisual
systems are standardized.
This procedure can provide high quality image transmission with effects similar to those of progressive and hierarchical
schemes. Minimal changes to H.261 (low cost), backward compatibility with existing terminals, and flexibility in image
quality versus transmission speed were the key considerations in its development.
NOTE – The encoder would set a previously unused bit in PTYPE to “0” when it transmits a still image (unused bits should be
set to “1”). A decoder that ignores this bit would receive the image as normal video. A decoder that goes into an error condition when this
bit is “0” would most likely freeze the previous video frame, and resume when this bit is reset to “1”. A decoder having this new capability
could display the image in a higher resolution, transfer the image to a separate graphics display and hold the image when video resumes,
print and/or save the image, etc.
D.2
Still image format
The still image format is four times the currently transmitted video format. If the video format is QCIF, then the still image is
a CIF frame. If the video format is CIF, which contains 352
×
288 luminance samples, then the still image contains 704
×
576
luminance samples, and a corresponding increase in the number of chrominance samples (a CCIR-601 frame).
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| H-8-4 | Broadband Two-Way Power Divider 2 MHz - 2 GHz |
| H-8-4BNC | Broadband Two-Way Power Divider 2 MHz - 2 GHz |
| H_8_4 | Broadband Two-Way Power Divider 2 MHz2 GHz |
| H1- | NPN/NPN resistor-equipped transistors R1 = 47 kohm, R2 = open |
| H1P | NPN/NPN resistor-equipped transistors R1 = 47 kohm, R2 = open |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| H2610(SERIES) | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Peripheral IC |
| H2610-10M | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Peripheral IC |
| H2610-210M | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Peripheral IC |
| H-2616-033 | 制造商:SAIA-BURGESS LEDEX AND DORMEYER PRODUCTS 功能描述:H-2616-033 / ROTARY / 3ER45o X3X4X6X9 |
| H-2617-026 | 制造商:SAIA-BURGESS LEDEX AND DORMEYER PRODUCTS 功能描述:H-2617-026 / ROTARY / 5ER45o X3X4X6X9 |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。