TI MM H.264 Encoder User Guide
Introduction

Table of Contents

Supported Features

TI’s embedded processors such as J721E having Imagination Technologies VXE384MP2 (ENCODER) for accelerating multimedia encode. "TI MM H.264 Video Encoder" supports:

  • H.264 encoding up to 1080p (1920x1080) resolutions
  • NV12 (two plane) format, 8-bit content support
  • Frame level encoding
  • I-Frame only encoding
    • This is the default mode supported in the driver
  • I & P Frame encoding
    • In order to enable I & P Frame encoding, driver code needs to be modified to set the required configuration
    • See Reconfiguring Driver below on how to change the default driver configuration
  • Two channel encoding up to 1080p (1920x1080) resolutions at 30fps.
    • Up to 8 channels of 1080p encoding can be supported at lower framerates assuming that the DDR_MCU2_1_NON_CACHE region is sized to have 176MB. If a smaller non-cache region is allocated in the memory map, the max number of channels and/or resolution of encoder will be lower.
    • In general it takes around 25 MB per channel of 1080p encoding/decoding, and will generally scale to other resolutions according to the megapixel size.
    • The following table lists tested sizes of DDR_MCU2_1_NON_CACHE and the observed max channels of 1920x1080 encoder.
      Channels DDR_MCU2_1_NON_CACHE
      5 112MB
      6 144MB
      7 144MB
      8 176MB
    • Simultaneous usecases with decoder may exceed the memory allocation if the DDR_MCU2_1_NON_CACHE region is too small for the number of encoder + decoder channels.
      • Please see SDK Documentation on the SDK memory map for more information on how to increase the carveout.
      • Be sure to manually update "mcu2_1/r5_mpu.xs" to correctly use MPU.setRegionMeta for the entire size of the mcu2_0 + mcu2+1 carveouts according to the memory map.
      • ex. if you're increasing the carveout from mcu2_1 carveout from 112MB to 240MB (16 of each reserved for mcu2_0 carveout, so total is 128MB vs 256MB)
        non_cache_base_addr = 0xD8000000;
        /* make DDR_MCU2_0_NON_CACHE, DDR_MCU2_1_NON_CACHE as non-cache */
        /* Note: MUST be 32MB aligned
        */
        attrs.enable = true;
        attrs.bufferable = false;
        attrs.cacheable = false;
        attrs.shareable = true;
        attrs.noExecute = true;
        attrs.accPerm = 1; /* RW at PL1 */
        attrs.tex = 0;
        attrs.subregionDisableMask = 0;
        -MPU.setRegionMeta(index++, non_cache_base_addr + 0*32*MB, MPU.RegionSize_32M, attrs);
        -MPU.setRegionMeta(index++, non_cache_base_addr + 1*32*MB, MPU.RegionSize_32M, attrs);
        -MPU.setRegionMeta(index++, non_cache_base_addr + 2*32*MB, MPU.RegionSize_32M, attrs);
        -MPU.setRegionMeta(index++, non_cache_base_addr + 3*32*MB, MPU.RegionSize_32M, attrs);
        +MPU.setRegionMeta(index++, non_cache_base_addr + 0*64*MB, MPU.RegionSize_64M, attrs);
        +MPU.setRegionMeta(index++, non_cache_base_addr + 1*64*MB, MPU.RegionSize_64M, attrs);
        +MPU.setRegionMeta(index++, non_cache_base_addr + 2*64*MB, MPU.RegionSize_64M, attrs);
        +MPU.setRegionMeta(index++, non_cache_base_addr + 3*64*MB, MPU.RegionSize_64M, attrs);
      • Be sure to follow the directions on updating and rebuilding the dtb/dtbo files that the gen_linker_mem_map.py script provides.

Non-Supported Features

"TI MM H.264 Video Encoder" does not support:

  • B-Frame encoding
  • Non NV12 pixel formats
  • Error recovery for crashes due to non-standard settings
  • Greater than two channels encoding

Reconfiguring Driver

File to change: psdk_rtos_auto_j7_xx/video_codec/ti-img-encode-decode/timmlib/encoder/mm_enc_create.c

Function: vxe_enc_s_fmt

Directory Structure

The main modules in Video Codec are listed below

Video Codec Modules Description
concerto Makefile build infrastructure
docs User documentation.
examples Application/Demo and Additional utility functions.
examples/apps/bios_cfg Application bios configuration for TI-RTOS on R5F and A72.
examples/apps/common Application common source code for TI-RTOS on R5F, and A72.
examples/apps/decoder Application/Demo sample application for single and multichannel usecase.
examples/apps/mcu2_0 R5F configuration.
examples/apps/mpu1 A72 configuration.
examples/utils Additional utility functions used.
lib MM Driver fw library.
makerules Build utility.
out Build/Generated files and executables.
ti-img-encode-decode MM Encoder Driver source code and firmware binary.
tools Scripts used to load and run the executables on CCS.

Known Limitations

  • QCIF resolution encoding not working
  • Only two simultaneous channels are supported with the current memory carveout setup for Video Codecs