1. A truck cargo box enclosure including a pair of support tracks adapted to mount to side rails of the cargo box, a plurality of flexible support rods for connecting to the support tracks, and a fabric siding including a U-shaped channel edge for engaging the support track on each side of the cargo box and adapted to connect to the support tracks and span the support rods in tension.
2. The truck cargo box enclosure of claim 1, wherein the flexible support rods are formed of multiple sections linked together.
3. The truck cargo box enclosure of claim 2, wherein the flexible support rods are longer than a width of the cargo box so as to describe an arch when connected to the support tracks.
4. The truck cargo box enclosure of claim 1, further including a door assembly for an end of the cargo box.
5. The truck cargo box enclosure of claim 4, wherein the door assembly is formed of fabric and integral with the fabric siding.
6. A cover adapted to enclose an open vehicle portion defined by a plurality of opposing wall sections, comprising:
a plurality of cover support tracks each adapted to attach to one of the plurality of opposing wall sections, each cover support track extending beyond an outer face of the wall section, and comprising a plurality of apertures and a depending flange;
a plurality of flexible support rods having an alignment tip and collar on each end; and
a fabric covering having a lateral edge comprising a channel section adapted to engage the depending flange of one of the pair of cover support tracks,
wherein the tips of the support rods are adapted to engage the apertures of support tracks on opposing wall sections, supported on the collars, to define a support framework, and the fabric covering is adapted to span at least a portion of the support framework in tension with the channel section engaging the depending flange.
7. The cover of claim 6, wherein the fabric covering comprises a second lateral edge comprising a second channel section, and wherein the channel sections are adapted to engage the depending flange of cover support tracks attached to opposing wall sections to draw the tent fabric in tension over the support rods.
8. The cover of claim 7, wherein the support rods are each formed of at least two sections removably connected.
9. A vehicle cargo box having a pair of parallel side rails and a cargo box cover comprising:
a cover support track affixed to each of the parallel side rails, each cover support track extending beyond an outer face of the side rail and having a depending lip;
a plurality of support rods engaging the cover support tracks to form a frame over the cargo box; and
a fabric cover spanning the frame and having lateral edges each comprising an inwardly directed U-shaped channel engaging the depending lip.
10. The vehicle cargo box of claim 9, wherein the cover support track further comprises a plurality of apertures and wherein the support rods are adapted to engage the apertures.
11. The vehicle cargo box of claim 10, wherein at least one of the plurality of support rods comprises a tip and a collar adapted to engage the support rod with an aperture.
12. The vehicle cargo box of claim 9, wherein the support rods are flexible and the frame describes an arch over the cargo box.
13. The vehicle cargo box of claim 12, wherein the fabric spans the frame in tension.
14. The vehicle cargo box of claim 9, wherein the fabric spans the frame in tension.
15. The vehicle cargo box of claim 9, wherein the support rods are formed of a plurality of connected sections.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A system for real time transmission of variable bit rate MPEG video traffic with consistent quality, comprising:
a video encoder for encoding video data;
an encoder buffer for storing encoded video data;
an encoder rate controller for estimating a number of bits quantized from a target quantization parameter during a frame of said video data corresponding to discrete cosine transform (DCT) coefficients of said frame, and for providing quantization parameters based on slice level to said encoder;
a channel rate controller for dynamically generating parameters for smoothing and bandwidth renegotiation corresponding to said number of bits generated from said encoder rate controller, wherein smoothing includes reducing a peak transmission rate to a sustainable transmission rate and smoothing a transmission rate to said sustainable transmission rate;
a network for generating negotiated parameters corresponding to said parameters generated from said channel rate controller; and
a counter for transmitting said video data stored in said encoder buffer through said network at a smoothed transmission rate, in response to said negotiated parameters.
2. The system of claim 1, wherein said channel rate controller generates the maximum number of bits capable of being generated and stored during said frame period corresponding to the negotiated parameters generated from said network.
3. The system of claim 2, wherein said channel rate controller determines an actual bit rate of said encoded video data transmitted to said network through the encoder buffer corresponding to the generated maximum number of bits.
4. The system of claim 3, wherein said channel rate controller is filled with bits to protect an underflow of said encoder buffer.
5. The system of claim 1, wherein said parameters for smoothing and bandwidth renegotiation generated from said channel rate controller comprise peak rate, sustainable rate, and maximum burst length.
6. The system of claim 2, wherein said encoder rate controller generates an actual number of bits quantized by the target quantization parameter during the frame corresponding to the maximum number of bits generated from the channel rate controller.
7. The system of claim 1, wherein the counter comprises a Leaky Bucket counter, wherein during the frame encoding period, the Leaky Bucket counter increases the number of bits and decreases the sustainable bits during the frame period.
8. The system of claim 1, wherein when said counter is full, the counter discards the data transferred from said encoder buffer.
9. The system of claim 1, wherein said network comprises an asynchronous transfer mode (ATM).
10. The system of claim 1, wherein said encoded video data comprises variable bit rate MPEG video data.
11. A method for transmission of variable bit rate MPEG video traffic with consistent quality, comprising the steps of:
encoding frames of video data and generating encoding information associated therewith;
estimating a number of bits quantized from a target quantization parameter during a given frame of said video data based on encoding information of the given frame;
estimating a maximum number of bits capable of being generated based on network traffic parameters and buffer sizes;
computing a target bit rate using the estimated number of bits quantized with the target quantization parameters and the estimated maximum number of bits;
generating quantization parameters to control the actual encoding rate, if necessary, so that a number of actual bits generated does not exceed the target bit rate; and
dynamically negotiating with a network to generate traffic parameters that are used for dynamically adjusting bandwidth and for dynamically smoothing a transmission rate, wherein a negotiated peak transmission rate is reduced to a sustainable transmission rate, and said transmission rate is smoothed to said sustainable transmission rate.
12. The method of claim 11, wherein the encoding information comprises DCT (discrete cosine transformation) coefficients.
13. The method of claim 11, wherein the step of generating quantization parameters to control the actual encoding rate comprises generating quantization parameters based on slice level.
14. The method of claim 11, wherein the traffic parameters comprise peak rate, sustainable rate and maximum burst length.
15. The method of claim 11, further comprising the step of protecting against an underflow in an encoder buffer by stuffing bits.
16. The method of claim 11, further comprising the step of generating the actual number of bits quantized by the target quantization parameter during the given frame corresponding to the estimated maximum number of bits.
17. A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform method steps for transmission of variable bit rate MPEG video traffic with consistent quality, the method steps comprising:
encoding frames of video data and generating encoding information associated therewith;
estimating a number of bits quantized from a target quantization parameter during a given frame of said video data based on encoding information of the given frame;
estimating a maximum number of bits capable of being generated based on network traffic parameters and buffer sizes;
computing a target bit rate using the estimated number of bits quantized with the target quantization parameters and the estimated maximum number of bits;
generating quantization parameters to control the actual encoding rate, if necessary, so that a number of actual bits generated does not exceed the target bit rate; and
dynamically negotiating with a network to generate traffic parameters that are used for dynamically adjusting bandwidth and for dynamically smoothing a transmission rate, wherein a negotiated peak transmission rate is reduced to a sustainable transmission rate, and said transmission rate is smoothed to said sustainable transmission rate.
18. The program storage device of claim 17, wherein the encoding information comprises DCT (discrete cosine transformation) coefficients.
19. The program storage device of claim 17, wherein the instructions for generating quantization parameters to control the actual encoding rate comprise instructions for generating quantization parameters based on slice level.
20. The program storage device of claim 17, wherein the traffic parameters comprise peak rate, sustainable rate and maximum burst length.
21. The program storage device of claim 17, further comprising instructions for performing the step of protecting against an underflow in an encoder buffer by stuffing bits.
22. The program storage device of claim 17, further comprising instructions for performing the step of generating the actual number of bits quantized by the target quantization parameter during the given frame corresponding to the estimated maximum number of bits.