[FFmpeg-devel] [PATCH 087/114] avcodec/vc1: Avoid code duplication when initializing VLCs
Jerome Borsboom
jerome.borsboom at carpalis.nl
Wed Nov 18 16:08:05 EET 2020
I don't think it is a good idea to change the format of the table to
something different than the tables in the SMPTE VC-1 documentation.
People fluent in this documentation have a hard time correlating the new
tables to the 'official' ones.
---
Regards,
Jerome
> This has been achieved by switching those VLCs that still used
> ff_init_vlc_sparse() to ff_init_vlc_lengths() even though the codes
> tables used uint8_t in these cases. But it allows to use one auxiliary
> function to initialize the VLCs and by using tables that interleave
> symbols and lengths said function only needs one parameter for the
> tables, not two. The only table that uses an uint16_t symbols table
> still has to be treated specially for this reason.
>
> The offsets table has been removed as a byproduct of these changes.
>
> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at gmail.com>
> ---
> libavcodec/vc1.c | 158 +++++++++++++++---------------------------
> libavcodec/vc1data.c | 159 +++++++++++++++++++++----------------------
> libavcodec/vc1data.h | 21 ++----
> 3 files changed, 138 insertions(+), 200 deletions(-)
>
...
>
> /* 4MV Block pattern VLC tables */
> -const uint8_t ff_vc1_4mv_block_pattern_codes[4][16] = {
> - { 14, 58, 59, 25, 12, 26, 15, 15, 13, 24, 27, 0, 28, 1, 2, 2 },
> - { 8, 18, 19, 4, 20, 5, 30, 11, 21, 31, 6, 12, 7, 13, 14, 0 },
> - { 15, 6, 7, 2, 8, 3, 28, 9, 10, 29, 4, 11, 5, 12, 13, 0 },
> - { 0, 11, 12, 4, 13, 5, 30, 16, 14, 31, 6, 17, 7, 18, 19, 10 }
> -};
> -const uint8_t ff_vc1_4mv_block_pattern_bits[4][16] = {
> - { 5, 6, 6, 5, 5, 5, 5, 4, 5, 5, 5, 3, 5, 3, 3, 2 },
> - { 4, 5, 5, 4, 5, 4, 5, 4, 5, 5, 4, 4, 4, 4, 4, 2 },
> - { 4, 4, 4, 4, 4, 4, 5, 4, 4, 5, 4, 4, 4, 4, 4, 3 },
> - { 2, 4, 4, 4, 4, 4, 5, 5, 4, 5, 4, 5, 4, 5, 5, 4 }
> +const uint8_t ff_vc1_4mv_block_pattern_tabs[4][16][2] = {
> + {
> + { 0x0B, 3 }, { 0x0D, 3 }, { 0x0E, 3 }, { 0x04, 5 }, { 0x08, 5 },
> + { 0x00, 5 }, { 0x06, 5 }, { 0x0F, 2 }, { 0x09, 5 }, { 0x03, 5 },
> + { 0x05, 5 }, { 0x0A, 5 }, { 0x0C, 5 }, { 0x01, 6 }, { 0x02, 6 },
> + { 0x07, 4 },
> + },
> + {
> + { 0x0F, 2 }, { 0x03, 4 }, { 0x05, 4 }, { 0x0A, 4 }, { 0x0C, 4 },
> + { 0x00, 4 }, { 0x01, 5 }, { 0x02, 5 }, { 0x04, 5 }, { 0x08, 5 },
> + { 0x07, 4 }, { 0x0B, 4 }, { 0x0D, 4 }, { 0x0E, 4 }, { 0x06, 5 },
> + { 0x09, 5 },
> + },
> + {
> + { 0x0F, 3 }, { 0x03, 4 }, { 0x05, 4 }, { 0x0A, 4 }, { 0x0C, 4 },
> + { 0x01, 4 }, { 0x02, 4 }, { 0x04, 4 }, { 0x07, 4 }, { 0x08, 4 },
> + { 0x0B, 4 }, { 0x0D, 4 }, { 0x0E, 4 }, { 0x06, 5 }, { 0x09, 5 },
> + { 0x00, 4 },
> + },
> + {
> + { 0x00, 2 }, { 0x03, 4 }, { 0x05, 4 }, { 0x0A, 4 }, { 0x0C, 4 },
> + { 0x07, 5 }, { 0x0B, 5 }, { 0x0D, 5 }, { 0x0E, 5 }, { 0x0F, 4 },
> + { 0x01, 4 }, { 0x02, 4 }, { 0x04, 4 }, { 0x08, 4 }, { 0x06, 5 },
> + { 0x09, 5 },
> + },
> };
>
> /* 2MV Block pattern VLC tables */
> -const uint8_t ff_vc1_2mv_block_pattern_codes[4][4] = {
> - { 2, 1, 0, 3 }, { 1, 0, 2, 3 }, { 2, 0, 3, 1 }, { 1, 3, 2, 0 }
> -};
> -
> -const uint8_t ff_vc1_2mv_block_pattern_bits[4][4] = {
> - { 2, 2, 2, 2 }, { 1, 2, 3, 3 }, { 3, 2, 3, 1 }, { 1, 3, 3, 2 }
> +const uint8_t ff_vc1_2mv_block_pattern_tabs[4][4][2] = {
> + { { 0x02, 2 }, { 0x01, 2 }, { 0x00, 2 }, { 0x03, 2 } },
> + { { 0x01, 2 }, { 0x02, 3 }, { 0x03, 3 }, { 0x00, 1 } },
> + { { 0x01, 2 }, { 0x00, 3 }, { 0x02, 3 }, { 0x03, 1 } },
> + { { 0x03, 2 }, { 0x02, 3 }, { 0x01, 3 }, { 0x00, 1 } },
> };
>
> /* Interlaced frame picture 4MV MBMODE VLC tables (tables 160-163) */
> @@ -350,46 +349,42 @@ const uint8_t ff_vc1_intfr_non4mv_mbmode_tabs[4][9][2] = {
>
> /* Interlaced field picture MBMODE VLC tables (p. 356 - 11.4.1, 11.4.2) */
> /* mixed-MV */
> -const uint8_t ff_vc1_if_mmv_mbmode_codes[8][8] = {
> - { 16, 17, 3, 3, 0, 5, 9, 2 },
> - { 8, 9, 3, 6, 7, 0, 5, 2 },
> - { 16, 17, 5, 3, 0, 3, 9, 2 },
> - { 56, 57, 15, 4, 5, 6, 29, 0 },
> - { 52, 53, 27, 14, 15, 2, 12, 0 },
> - { 56, 57, 29, 5, 6, 0, 15, 4 },
> - { 16, 17, 6, 7, 0, 1, 9, 5 },
> - { 56, 57, 0, 5, 6, 29, 4, 15 }
> -};
> -const uint8_t ff_vc1_if_mmv_mbmode_bits[8][8] = {
> - { 6, 6, 2, 3, 2, 4, 5, 2 },
> - { 5, 5, 3, 3, 3, 2, 4, 2 },
> - { 6, 6, 4, 3, 2, 2, 5, 2 },
> - { 6, 6, 4, 3, 3, 3, 5, 1 },
> - { 6, 6, 5, 4, 4, 2, 4, 1 },
> - { 6, 6, 5, 3, 3, 1, 4, 3 },
> - { 5, 5, 3, 3, 2, 2, 4, 3 },
> - { 6, 6, 1, 3, 3, 5, 3, 4 }
> +const uint8_t ff_vc1_if_mmv_mbmode_tabs[8][8][2] = {
> + { { 0x04, 2 }, { 0x00, 6 }, { 0x01, 6 }, { 0x06, 5 },
> + { 0x05, 4 }, { 0x03, 3 }, { 0x07, 2 }, { 0x02, 2 } },
> + { { 0x05, 2 }, { 0x00, 5 }, { 0x01, 5 }, { 0x06, 4 },
> + { 0x02, 3 }, { 0x07, 2 }, { 0x03, 3 }, { 0x04, 3 } },
> + { { 0x04, 2 }, { 0x00, 6 }, { 0x01, 6 }, { 0x06, 5 },
> + { 0x02, 4 }, { 0x03, 3 }, { 0x07, 2 }, { 0x05, 2 } },
> + { { 0x07, 1 }, { 0x03, 3 }, { 0x04, 3 }, { 0x05, 3 },
> + { 0x00, 6 }, { 0x01, 6 }, { 0x06, 5 }, { 0x02, 4 } },
> + { { 0x07, 1 }, { 0x05, 2 }, { 0x06, 4 }, { 0x00, 6 },
> + { 0x01, 6 }, { 0x02, 5 }, { 0x03, 4 }, { 0x04, 4 } },
> + { { 0x05, 1 }, { 0x07, 3 }, { 0x03, 3 }, { 0x04, 3 },
> + { 0x00, 6 }, { 0x01, 6 }, { 0x02, 5 }, { 0x06, 4 } },
> + { { 0x04, 2 }, { 0x05, 2 }, { 0x00, 5 }, { 0x01, 5 },
> + { 0x06, 4 }, { 0x07, 3 }, { 0x02, 3 }, { 0x03, 3 } },
> + { { 0x02, 1 }, { 0x06, 3 }, { 0x03, 3 }, { 0x04, 3 },
> + { 0x00, 6 }, { 0x01, 6 }, { 0x05, 5 }, { 0x07, 4 } },
> };
> /* 1MV */
> -const uint8_t ff_vc1_if_1mv_mbmode_codes[8][6] = {
> - { 0, 1, 1, 1, 1, 1 },
> - { 0, 1, 1, 1, 1, 1 },
> - { 16, 17, 3, 0, 9, 5 },
> - { 20, 21, 3, 11, 0, 4 },
> - { 4, 5, 2, 3, 3, 0 },
> - { 4, 5, 3, 2, 0, 3 },
> - { 0, 1, 1, 1, 1, 1 },
> - { 16, 17, 9, 5, 3, 0 }
> -};
> -const uint8_t ff_vc1_if_1mv_mbmode_bits[8][6] = {
> - { 5, 5, 1, 3, 2, 4 },
> - { 5, 5, 1, 2, 3, 4 },
> - { 5, 5, 2, 1, 4, 3 },
> - { 5, 5, 2, 4, 1, 3 },
> - { 4, 4, 2, 3, 2, 2 },
> - { 4, 4, 3, 2, 2, 2 },
> - { 5, 5, 3, 4, 1, 2 },
> - { 5, 5, 4, 3, 2, 1 }
> +const uint8_t ff_vc1_if_1mv_mbmode_tabs[8][6][2] = {
> + { { 0x00, 5 }, { 0x01, 5 }, { 0x05, 4 },
> + { 0x03, 3 }, { 0x04, 2 }, { 0x02, 1 } },
> + { { 0x00, 5 }, { 0x01, 5 }, { 0x05, 4 },
> + { 0x04, 3 }, { 0x03, 2 }, { 0x02, 1 } },
> + { { 0x03, 1 }, { 0x00, 5 }, { 0x01, 5 },
> + { 0x04, 4 }, { 0x05, 3 }, { 0x02, 2 } },
> + { { 0x04, 1 }, { 0x05, 3 }, { 0x00, 5 },
> + { 0x01, 5 }, { 0x03, 4 }, { 0x02, 2 } },
> + { { 0x05, 2 }, { 0x00, 4 }, { 0x01, 4 },
> + { 0x03, 3 }, { 0x02, 2 }, { 0x04, 2 } },
> + { { 0x04, 2 }, { 0x00, 4 }, { 0x01, 4 },
> + { 0x02, 3 }, { 0x03, 2 }, { 0x05, 2 } },
> + { { 0x00, 5 }, { 0x01, 5 }, { 0x03, 4 },
> + { 0x02, 3 }, { 0x05, 2 }, { 0x04, 1 } },
> + { { 0x05, 1 }, { 0x00, 5 }, { 0x01, 5 },
> + { 0x02, 4 }, { 0x03, 3 }, { 0x04, 2 } },
> };
...
> --
> 2.25.1
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