for ABSDATA mode, so segment loop filter level always fall in valid
range for both Absolute and delta modes.
Change-Id: If90df3411479533dbdab63f8ae088d2f5dd174a9
The qindex for a segment was not clamped in ABSDATA mode, which may
cause invalid memory access if an ill-formed stream has a negative
value in ABSDATA mode. This commit added clamp to make sure qindex
for a segment always fall into valid range.
Change-Id: I0a74d00f4ef40aec7edaeca1d03c8645e23ab08c
Optimizing 2 functions to process 32 elements in parallel instead of 16:
1. vp9_sub_pixel_variance64x64
2. vp9_sub_pixel_variance32x32
both of those function were calling vp9_sub_pixel_variance16xh_ssse3
instead of calling that function, it calls vp9_sub_pixel_variance32xh_avx2
that is written in avx2 and process 32 elements in parallel.
This Optimization gave 70% function level gain and 2% user level gain
Change-Id: I4f5cb386b346ff6c878a094e1c3b37e418e50bde
Optimizing all SSSE3 assembly for convolution:
1. vp9_filter_block1d4_h8_sse2
2. vp9_filter_block1d8_h8_sse2
3. vp9_filter_block1d16_h8_sse2
4. vp9_filter_block1d4_v8_sse2
5. vp9_filter_block1d8_v8_sse2
6. vp9_filter_block1d16_v8_sse2
my optimization include:
-processing 2x8 elements in one 128 bit register instead of processing
8 elements in one 128 bit register.
-removing unecessary loads.
This optimization gives between 2.4% user level gain for 480p input
and 1.6% user level gain for 720p.
This Optimization is done only for 64 bit
Change-Id: Ic07fce2f9360329b4f2d956efda1480ae958766b
Added support for external frame buffers to libvpx's VP9 decoder.
If the external frame buffer functions are set then libvpx will
call the get function whenever it needs a new frame buffer to
decode a frame into. And it will call the release function
whenever there are no more references to that buffer.
Change-Id: Id2934d005f606af6e052fb6db0d5b7c02f567522
Prior to this commit, both encoder and decoder reset mode/mv info from
previous frame in error resilient mode to ensure bitstreams are able to
decode when there is loss of frame in decoder side. However, this is
not necessary. This commit changed to remove the reset, so encoder can
continue to use mode/mv/partition information from previously encoded
frame without affecting decodeablilty under loss of frame.
Change-Id: I0279f862900dc647fb471ae3389770bb1b9f454f
Two convolve functions were optimized for AVX2:
1. vp9_filter_block1d16_h8
2. vp9_filter_block1d16_v8
vp9_filter_block1d16_v8 was optimized for AVX2 by reducing the number of
loop strides by half, two strides were processed in parallel.
vp9_filter_block1d16_v8 was also optimized in the same way also some of the
loads were being done outside of the loop and by that preventing redundant
loads.
This Optimization gives 43% function level gain and 1.3% user level gain.
Now can be compiled in Windows
Change-Id: I2714124cfb0c14a77d7a0ce126a20db92ffbf92c
This CL changes libvpx to call a function when a frame buffer
is needed for decode. Libvpx will call a release callback when
no other frames reference the frame buffer. This CL adds a
default implementation of the frame buffer callbacks. Currently
only VP9 is supported. A future CL will add support for
applications to supply their own frame buffer callbacks.
Change-Id: I1405a320118f1cdd95f80c670d52b085a62cb10d
This patch adds a buffer-based rate control for temporal layers,
under CBR mode.
Added vpx_temporal_scalable_patters.c encoder for testing temporal
layers, for both vp9 and vp8 (replaces the old vp8_scalable_patterns).
Updated datarate unittest with tests for temporal layer rate-targeting.
Change-Id: I8900a854288b9354d9c697cfeb0243a9fd6790b1
This isn't strictly necessary, but makes the file more consistent
with the other arm assembly source files.
Change-Id: I245c9677d89e0ab3f31991e473764858af35b180
avoid wrapping msvc includes with extern "C"; this breaks some visual
studio builds of the (c++) tests.
Change-Id: Ie8062d55d4f4c049f6cd360a36da6a67607df132
This patch added ssse3 optimization of bilinear sub-pixel filters.
The real time encoder was speeded up by ~1%.
Change-Id: Ie82e98976f411183cb8c61ab8d2ba0276e55a338
The new implementation disagrees when the argument is equal to 2**n but
that is never called in practice and based on how it is used the new
implementation is correct in that case.
Change-Id: Ifbac4ad87d459fe6bd2fd0f400c0340f96617342
Using bilinear filters could speed up the codec in real-time mode.
This patch added sse2 optimizations of bilinear filters that
operate on different-sized blocks.
Tests showed that the real-time encoder was speeded up by 3%.
Change-Id: If99a7ee4385fcc225c3ee7445d962d5752e57c3f
This patch adds a buffer-based rate control for temporal layers,
under CBR mode.
Added vpx_temporal_scalable_patters.c encoder for testing temporal
layers, for both vp9 and vp8 (replaces the old vp8_scalable_patterns).
Updated datarate unittest with tests for temporal layer rate-targeting.
Change-Id: I9cb6cce2494390ae6096ee17774af7fb9308bde7
As pointed out by Dmitry and James, "partial" is a Microsoft-
specific c++ keyword, and it is renamed.
Change-Id: Ia0fc11ceb89e54b3195287f89f7e26edbbe9beb8
Implemented parallel loopfiltering, which uses existing tile-
decoding threads. Each thread works on one row, and when that row
is loopfiltered, it moves to next unattended row. To ensure the
correct filtering order, threads are synchronized and one
superblock is filtered only if the superblocks it depends on are
filtered already.
To reduce synchronization overhead and speed up the decoder, we use
nsync > 1 for high resolution.
Performance tests:
1. on desktop:
8-tile 4k video using 8 threads, speedup: 70% - 80%
4-tile HD video using 4 threads, speedup: ~35%
2. on mobile device(Nexus 7):
4-tile 1080p video using 4 threads, speedup: 18% - 25%
4-tile 1080p video using 2 threads, speedup: 10% - 15%
Change-Id: If54b4a11960dd706c22d5ad145ad94156031f36a
This patch only works if the video is a width and height that are both
a multiple of 32.. It sets every partition to 16x16, and does INTRADC
only on the first frame and ZEROMV on every other frame. It always does
does the largest possible transform, and loop filter level is set to 4.
Was ~20% faster than speed -5 of vp8
Now 20% slower but adds motion search ( every block ), nearest, near
and zeromv
The SVC test was changed because - while this realtime mode produces
bad quality albeit quickly, it isn't obeying all the rules it should
about which frames are available.
Change-Id: I235c0b22573957986d41497dfb84568ec1dec8c7
Encoder's boarder is still 160, while decoder's boarder will be 32.
With on demand and separate boarder buffer for boarder extension.
The decoder's boarder does not need to to 160 anymore.
Change-Id: I93d5aaff15a33a2213e9761eaa37c5f2870747db
This commit deprecates the use of best_mv from encoding and bit-stream
writing stages. It hence removes the definition from MACROBLOCKD.
Change-Id: I8e5302775a2aa4a18900726df407bff881f2dfb1
This commit further optimizes SSE2 operations in the second 1-D
inverse 16x16 DCT, with (<10) non-zero coefficients. The average
runtime of this module goes down from 779 cycles -> 725 cycles.
Change-Id: Iac31b123640d9b1e8f906e770702936b71f0ba7f
Optimizing all SSSE3 assembly for convolution:
1. vp9_filter_block1d4_h8_sse2
2. vp9_filter_block1d8_h8_sse2
3. vp9_filter_block1d16_h8_sse2
4. vp9_filter_block1d4_v8_sse2
5. vp9_filter_block1d8_v8_sse2
6. vp9_filter_block1d16_v8_sse2
my optimization include:
-processing 2x8 elements in one 128 bit register instead of processing
8 elements in one 128 bit register.
-removing unecessary loads.
This optimization gives between 2.4% user level gain for 480p input
and 1.6% user level gain for 720p.
This Optimization done only for 64bit.
Change-Id: Icb586dc0c938b56699864fcee6c52fd43b36b969
This commit is the first patch optimizing SSE2 implementation of inverse
16x16 DCT with <10 non-zero coefficients. It focused on the first 1-D (row)
transformation. It exploits the fact that only top-left 4x4 block contains
non-zero coefficients, in a 2-D inverse 16x16 DCT with <10 coeffients.
The average runtime of idct16x16_10 unit is reduced from
883 cycles -> 779 cycles (12% faster).
For pedestrian_area_1080p 300 frames at 4000 kbps, the speed 2 runtime goes
down from 310651 ms -> 305910 ms. The decoding speed goes up from
80.37 fps -> 80.87 fps.
Change-Id: Ic6f3ac5a637a76c07ba73ddaafe318a699fea645
Optimizing the variance functions: vp9_variance16x16, vp9_variance32x32,
vp9_variance64x64, vp9_variance32x16, vp9_variance64x32,
vp9_mse16x16 by migrating to AVX2
some of the functions were optimized by processing 32 elements instead of 16.
some of the functions were optimized by processing 2 loop strides of 16
elements in a single 256 bit register
This optimization gives between 2.4% - 2.7% user level performance gain
and 42% function level gain.
Change-Id: I265ae08a2b0196057a224a86450153ef3aebd85d
This commit adds input/output ports for IDCT8_1D macro function to
provide more flexibility in variable use. It allows to skip several
buffer swap operations.
Change-Id: I21f3450509537322293043b3281bfd3949868677
Adding RefBuffer to simplify reference buffer management. The struct has a
pointer to image data and scale factors relative to the current frame.
Change-Id: If38eb1491ff687cc11428aee339f3e052e2c5d9e
This commit merges the initial buffer swap operations in idct8_1d_sse2
into the array transpose step, hence reducing number of instructions
therein.
Change-Id: I219f6f50813390d2ec3ee37eecf2a4a2b44ae479
This commit optimizes the SSE2 implmentation of idct8x8_10. It exploits
the fact that only top-left 4x4 block contains non-zero coefficients,
and hence reduces the instructions needed.
The runtime of idct8x8_10_sse2 goes down from 216 to 198 CPU cycles,
estimated by averaging over 100000 runs. For pedestrian_area_1080p 300
frames coded at 4000kbps, the average decoding speed goes up from
79.3 fps to 79.7 fps.
Change-Id: I6d277bbaa3ec9e1562667906975bae06904cb180
Moving back to scale_factors struct. We don't need anymore x_offset_q4 and
y_offset_q4 because both values are calculated locally inside vp9_scale_mv
function.
Change-Id: I78a2122ba253c428a14558bda0e78ece738d2b5b
Before mv scaling it is required to calculate x_offset_q4/y_offset_q4
by calling set_scaled_offsets(). Now offset configuration can not be
missed because it happens just before scale_mv().
Change-Id: I7dd1a85b85811a6cc67c46c9b01e6ccbbb06ce3a
MV struct was ussed to indicate the postition of a MI_BLOCK with row
and col components. The expression was confusing, this commit added a
new stucture "POSITION" with row and col component to better describe
the position of a mi_block.
Change-Id: I59fdd4b45010fe7d85a8db22a55503265c4f5b2b
Making overall logic more clear, moving "hacked" calculation of base filter
array pointer to get_filter_base() function.
Change-Id: Ibbd38a9f937e48d35bbbfef3ad933ab36664cccb
Add a full range motion search for regular block sizes. This runs
exhaustive search within the given reference area. This commit further
optimizes the search process by combining 4 points test into one
pipeline, which gives 30% speed-up as compared to run each individual
point at a time.
This full range search serves as a best possible motion search reference.
When replacing the diamond search with full range search, the speed 0
runtime of bus CIF at 2000 kbps goes from 153872ms to 623051ms. The
compression performance compared to speed 0 setting gains 0.585% for
derf set.
Change-Id: Ieef1225216b0b86b4ac4872fa7fb9e18bf2eabb3
Removed calls to vp9_update_mode_info_border since
they immediately followed code that initialized the
entire buffer to 0.
Change-Id: Ife06794daa20439a0b607a83a87f88df59afac40
- Disable mode info update in case where current frame is coded
as "show existing frame".
- Should fix issue 676.
Change-Id: Ibee681850eb307f982da6528d3e31cb94f881c08
The old code would start in a mixed state, where all the reference
frames were pointing to frame buffer 0, but the reference counts
were 0. This is why we needed special code for the first frame.
Change-Id: I734961012917654ff8c0c8b317aac00ab75ded1a
Using get_plane_block_size() instead of manipulation with subsampling
values, calculating all required values only once without redundant calls
to b_width_log2().
Change-Id: I00303f2a0926f9c4cb17f34591adda60615f8919
Jingning saw bitstream change with this patch. It could be true
that (mask_16x16_0 & 1) is 1, but (mask_16x16_1 & 1) is 0 in some
edge cases.
This reverts commit 8f05e70340.
Change-Id: I0a529435ce816a1e14653eb510d5090de276070a
In the decoder we don't need to save eobs, we can pass eob as an argument.
That's why removing eob arrays from VP9Decompressor and TileWorkerData,
and moving eob pointer from macroblockd_plane to macroblock_plane.
Change-Id: I8eb919acc837acfb3abdd8319af63d1bbca8217a
The performance gain of idct16x16_10_add_sse2 function is not
noticeable. However since both functions use the IDCT16_1D,
idct16x16_10_add_sse2 should be modified as well.
Tested with: park_joy_420_720p50.y4m
Change-Id: I02b957e36fcf997c677d15baf496533895271bff
Considering a horizontal edge, if mask_16x16 is 1 for an even-
indexed 8x8 block, then mask_16x16 is 1 for next 8x8 block in
same row. Similiar to a verticle edge, if mask_16x16 is 1 for
an even-rowed 8x8 block, then mask_16x16 is 1 for the 8x8 block
right below it in next raw. Based on that, the mask_16x16 checking
can be simplified to save cycles. The corresponding 8-pixel
vp9_mb_lpf_horizontal_edge code can also be removed.
Change-Id: Ic3fe7a5674322239208cbe2731dc3216ce2084f3
We only need qcoeff buffers in the encoder. Reducing TileWorkerData struct
and VP9Decompressor struct sizes by 24K.
Change-Id: Id148868461f7ffa3d3dd634b371503ae9c57e207
vp9_idct32x32_34_add_sse2:
speedup: 1.472
IDCT32_1D_34 and MULTIPLICATION_AND_ADD_2 are optimized
based on the fact that Only upper-left 8x8 has
non-zero values.
vp9_idct32x32_1024_add_sse2:
speedup: 1.032
Tested with: park_joy_420_720p50.y4m
Change-Id: I8670ce547552b48695049de298e2fc46ce28dfbc
The idea here is to allow "in frame" adjustment of the final Q
value used to encode each SB64, using segmentation.
There is also adjustment of the rd mult in regions of overspend.
Activated using aq_mode=2
Change-Id: I2f140cd898c9f877c32cd6d2e667f5e11ada4b1c
The decoder will construct inter predictor using lazy border extension,
while the encoder, going with multiple runs of motion search in the rate-
distortion optimization loop for each block, does border extension at
frame level. This commit makes separate the inter predictors for encoder
and decoder, respectively.
Change-Id: Ieca2fecba3a7201a6d64ef9f219e5d91e50559c3
This commit takes out vp9_extend_frame_borders from
vp9_setup_scale_factors.
The refactoring is for the preparation of the use of lazy border
extension at decoder. This makes it necessary to handle border
extension separately at encoder/decoder. The use of
vp9_extend_frame_borders will be removed, when lazy border extension
is ready.
Change-Id: Ia3baba3d179d5f11eee1634f19b3b319d2a59186
This patch followed "Add filter_selectively_vert_row2 to enable
parallel loopfiltering" commit, and added x86 SSE2 optimization
to do 16-pixel filtering in parallel. For other optimizations
(neon and dspr2), current 16-pixel functions were done by calling
8-pixel functions twice, and real 16-pixel functions could be added
later.
Decoder speedup:
tulip clip: 2% speed gain;
old_town_cross: 1.2% speed gain;
bus: 2% speed gain.
Change-Id: I4818a0c72f84b34f5fe678e496cf4a10238574b7
Both functions have no relation to motion vectors, so moving them from
vp9_findnearmv.h to vp9_blockd.h.
Change-Id: I74f524267886ab0fff4a2da793a10c906ed0f43a
Added filter_selectively_vert_row2 to be ready for parallel
loopfiltering in vertical direction. This change did 2-row
filtering at a time. If 2 vertically adjacent 8x8 blocks do same
type of filtering, we can do 16-pixel filtering in parallel.
Next, we need to provide 16-pixel loopfiltering functions in c
and optimized versions for codec speedup.
Change-Id: Idf97bbdd70566e55bd30e1fd25cb8544e33291be
Add support to do 16 pixel horizontal filtering in Neon.
Nexus devices saw about 0.5% decode speed increase.
Change-Id: I2993f6c2d49f31fa74976879eeaa289fd3f4e15d
This function is called from vp9_setup_past_independence() which is called
before the modified piece of code. Moving reset of inter_mode_probs into
vp9_init_mbmode_probs() for consistency.
Change-Id: Ib188e8798e1fbe15407fd501406761b746fdda95
Although no mismatch was indicated for 8/16 wide sub-pixel filters
in issue 661, they had similar problems that could cause mismatch
potentially. This patch fixed calculations in HORIZx8/16
and VERTx8/16.
Change-Id: I169961c9d40a20340995b7d22aafc89ccf30bfca
In commit "3d50da5397d20abc932d81453b26cde758293a40", the stack
pointer was modified while aligning the stack, and it needed to
be pop out at the end.
Change-Id: I062971e195f1f2ab9d0ab5fb84dcf215a0fcaa67
This patch fixed issue 661: "Decoder produces mismatched outputs
with ssse3 enabled and disabled." In sub-pixel filters, a pixel
value was multiplied by a filter coefficient, and the results
were added up. The order of adding up these multiplications had to
be arranged carefully to prevent incorrect overflowing.
Change-Id: Id08af4200fea9e1b896fc40157b8651c2c7e80f2
Reversing bit order of partition_context_lookup, and modifying accordingly
update_partition_context() and partition_plane_context().
Change-Id: I64a11f1a94962a3bf217de2f50698cb781db71a5
This rebase is a better implementation of the previous ones.
Modifications are done to reduce the total clock cycle.
Speedup: 1.341
Compiled with -O3
Tested with: park_joy_420_720p50.y4m
Change-Id: I940eaf283f60597ca0d9d2e13d518878d55ff02d
Since they used in encoder only. This commit also re-order includes
for the files that include vp9_extend.h
Change-Id: I929fc113f2135d3198cd1fc6a17434e5a2f8a459
This patch followed "Rewrite filter_selectively_horiz for parallel
loopfiltering" commit, and added x86 SSE2 optimization to do
16-pixel filtering in parallel. Also, corrected the declaration
of aligned arrays. For 8-pixel-in-parallel case, improved the
calculation of the masks and filters. Updated the threshold loading
since the thresholds were already duplicated. Updated neon C functions
to call neon loopfilters twice.
Using tulip clip, tests showed it gave a ~1.5% decoder speed gain.
Change-Id: Id02638626ac27a4b0e0b09d71792a24c0499bd35
Separate the rounding and right shift operations of forward transform
from those of inverse transform. Take out the assertion check from
inverse transforms. If the transform coefficients were constructed to
cause intermediate steps of inverse transform overflow, the codec will
just let it overflow without breaking the decoding flow.
Change-Id: I73cfc3706c4e840fc543a77cbc4cdb0b05d07730
on arm until we implenment real vp9_idct32x32_34_add_neon.
This issue is due to commit 47665452f0
Merge "Add 32x32 idct function for eob<=34 case".
Change-Id: I56b5f0abc20e7dd1bba521f78a995e85d65ea296
Simplifies the code by implementing band mapping with static arrays.
A lot of the code complexity introduced in a previous patch
disappears.
Change-Id: Ia3fac36e594fb5ad2d55ae141c58bba4c55c2d28
As Jim suggested, 1D array was used to store filter levels instead
of 2D array. This used shift_y in setup_mask directly, and saved
few cycles.
Change-Id: If61ab298784861f1806b1cd396d4e4e2e0f097b9
Implements scan order to band map with arrays in both the encoder
and decoder to remove conditional statements.
Encoding seems to be about 1% faster at speed 0, tested on football.
Decoding seems to be about 0.5-1% faster on a set of 25 videos.
Change-Id: Idb233ca0b9e0efd790e30880642e8717e1c5c8dd
Added loop filter mask checking, and made the caller function
ready for implementation of parallel loopfiltering in horizontal
direction.
Next, we need to go through the loopfilter functions (both c and
optimized versions), and provide 16-byte wide loopfiltering for
each filter type.
Change-Id: Ifef47e7ef9086ebc2fd6ca7ede8f27c9bbf79e66
Make the macroblockd_plane contain dynamic buffer pointers instead
static pointers to the memory space allocated therein. The decoder
uses the buffer allocated in pbi, while encoder will use a dual
buffer approach for rate-distortion optimization search.
Change-Id: Ie6f24be2dcda35df7c15b4014e5ccf236fb3f76c
Inlining set_contexts_on_border() into set_contexts(). The only difference
is the additional check that "has_eob != 0" in addition to
"xd->mb_to_right_edge < 0" and "xd->mb_to_right_edge < 0". If has_eob == 0
then memset does the right thing and works faster.
Change-Id: I5206f767d729f758b14c667592b7034df4837d0e
This patch continued the work done in "Rewrite loop_filter_info_n
struct"(commit:00dbd369c70270428d56da6d15ea5486fc821c52) to further
improve loopfilter function.
1. Instead of storing pointers to thresholds, store loopfilter
levels within 64x64 SB;
2. Since loopfilter levels are already calculated in setup_mask,
we don't need call build_lfi to look up them again. Just save
loopfilter levels in setup_mask.
3. Reorganized and simplified filter_block_plane().
Tests showed a ~0.8% decoder speedup.
Change-Id: I723c7779738bbc2afcb9afa2c6f78580ee6c3af7
SVC multiple layer per frame encoding is invoked with vpx_svc_init and
vpx_svc_encode. These interfaces are designed to be invoked from ffmpeg.
Additional improvements:
- make dummy frame handling a bit more explicit
- fixed bug with single layer encodes
- track individual frame sizes and psnrs instead of averages
- parameterized quantizer, 16th scalefactors, more logging,
- enabled single layer encodes to generate baseline
- include new mode for 3 layer I frame with 5 total layers
Change-Id: I46cfa600d102e208c6af8acd6132e0cc25cda8d4
Removing special case handling from vp9_tree_probs_from_distribution(),
tree_merge_probs(), and vp9_tokens_from_tree_offset() functions. Replacing
inter_mode_offset() function with macro INTER_OFFSET which is used now for
vp9_inter_mode_tree definition.
Change-Id: Iff75a1499d460beb949ece543389c8754deaf178
We only update partition_probs for inter frames but they are constant
for key frames. It is not necessary to have constants inside frame
context and copy them every time. This change reduces FRAME_CONTEXT size
by at least 48 bytes.
Change-Id: If70a53be51043f37fe7d113853217937710932a7
We don't have to calculate 'new' probability in convert_distribution()
because it is enough to calculate only 'new' counters which could be used
to calculate probability if necessary. That's why removing a lot of unused
temporary probability arrays and reducing number of get_binary_prob()
calls.
Change-Id: I4e14eb7203d1ace61bbddefd6b9b6326be83ba63
This CL contains two AVX2 optimized loop filter functions,
mb_lpf_horizontal_edge_w_avx2_8 and mb_lpf_horizontal_edge_w_avx2_16.
Change-Id: I604e4fe6e99752b7800c2ea98721d97f7e0b931b
"<< SUBPEL_BITS" needs to be added in the calculation. Call
set_scaled_offsets() to calculate x_offset_q4 and y_offset_q4.
Change-Id: Ied130ea771510e918f51cd1dc3abe57f4c0962b5
It is enough to check just block type: intra or inter. Intra block implies
intra prediction mode, and inter block implies inter mode.
Change-Id: I3cf98731a3935f670a3cd8e2b2443483eb944be4
replaces use of cur_tile_mi_(row|col)_(start|end) by VP9_COMMON, making
it less stateful and more reusable for parallel tile decoding
Change-Id: I1df09382b4567a0e5f4434825d47c79afe2399be
Restructured the storing of loopfilter information. Deleted
loop_filter_info struct and reduced copying happened in every
superblock.
Tests showed a 0.5% ~ 0.8% decoder speed gain.
Change-Id: Ie6a8e46bae71dc3a3cd8c6054f5de540b8e0ef5e
update_partition_context / partition_plane_context: this will allow for
separate storage to be used in tile decoding
Change-Id: Ie0bc393531ab7e9d2ce35c95111849b294aad4ed
When only upper-left 8x8 area has non-zero dct coefficients, we
could skip 1D IDCT for 9th to 32th rows to save operations. This
function is called when eob <= 34.
Change-Id: I9684b75947bdde346cfe3720f08a953aa7a13fb5