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FFmpeg/libavcodec/eatgq.c
Andreas Rheinhardt 4243da4ff4 avcodec/codec_internal: Use union for FFCodec decode/encode callbacks
This is possible, because every given FFCodec has to implement
exactly one of these. Doing so decreases sizeof(FFCodec) and
therefore decreases the size of the binary.
Notice that in case of position-independent code the decrease
is in .data.rel.ro, so that this translates to decreased
memory consumption.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-04-05 20:02:37 +02:00

260 lines
8.4 KiB
C

/*
* Electronic Arts TGQ Video Decoder
* Copyright (c) 2007-2008 Peter Ross <pross@xvid.org>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* Electronic Arts TGQ Video Decoder
* @author Peter Ross <pross@xvid.org>
*
* Technical details here:
* http://wiki.multimedia.cx/index.php?title=Electronic_Arts_TGQ
*/
#define BITSTREAM_READER_LE
#include "libavutil/mem_internal.h"
#include "aandcttab.h"
#include "avcodec.h"
#include "bytestream.h"
#include "codec_internal.h"
#include "eaidct.h"
#include "get_bits.h"
#include "idctdsp.h"
#include "internal.h"
typedef struct TgqContext {
AVCodecContext *avctx;
int width, height;
ScanTable scantable;
int qtable[64];
DECLARE_ALIGNED(16, int16_t, block)[6][64];
GetByteContext gb;
} TgqContext;
static av_cold int tgq_decode_init(AVCodecContext *avctx)
{
TgqContext *s = avctx->priv_data;
uint8_t idct_permutation[64];
s->avctx = avctx;
ff_init_scantable_permutation(idct_permutation, FF_IDCT_PERM_NONE);
ff_init_scantable(idct_permutation, &s->scantable, ff_zigzag_direct);
avctx->framerate = (AVRational){ 15, 1 };
avctx->pix_fmt = AV_PIX_FMT_YUV420P;
return 0;
}
static void tgq_decode_block(TgqContext *s, int16_t block[64], GetBitContext *gb)
{
uint8_t *perm = s->scantable.permutated;
int i, j, value;
block[0] = get_sbits(gb, 8) * s->qtable[0];
for (i = 1; i < 64;) {
switch (show_bits(gb, 3)) {
case 4:
block[perm[i++]] = 0;
case 0:
block[perm[i++]] = 0;
skip_bits(gb, 3);
break;
case 5:
case 1:
skip_bits(gb, 2);
value = get_bits(gb, 6);
for (j = 0; j < value; j++)
block[perm[i++]] = 0;
break;
case 6:
skip_bits(gb, 3);
block[perm[i]] = -s->qtable[perm[i]];
i++;
break;
case 2:
skip_bits(gb, 3);
block[perm[i]] = s->qtable[perm[i]];
i++;
break;
case 7: // 111b
case 3: // 011b
skip_bits(gb, 2);
if (show_bits(gb, 6) == 0x3F) {
skip_bits(gb, 6);
block[perm[i]] = get_sbits(gb, 8) * s->qtable[perm[i]];
} else {
block[perm[i]] = get_sbits(gb, 6) * s->qtable[perm[i]];
}
i++;
break;
}
}
block[0] += 128 << 4;
}
static void tgq_idct_put_mb(TgqContext *s, int16_t (*block)[64], AVFrame *frame,
int mb_x, int mb_y)
{
ptrdiff_t linesize = frame->linesize[0];
uint8_t *dest_y = frame->data[0] + (mb_y * 16 * linesize) + mb_x * 16;
uint8_t *dest_cb = frame->data[1] + (mb_y * 8 * frame->linesize[1]) + mb_x * 8;
uint8_t *dest_cr = frame->data[2] + (mb_y * 8 * frame->linesize[2]) + mb_x * 8;
ff_ea_idct_put_c(dest_y , linesize, block[0]);
ff_ea_idct_put_c(dest_y + 8, linesize, block[1]);
ff_ea_idct_put_c(dest_y + 8 * linesize , linesize, block[2]);
ff_ea_idct_put_c(dest_y + 8 * linesize + 8, linesize, block[3]);
if (!(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {
ff_ea_idct_put_c(dest_cb, frame->linesize[1], block[4]);
ff_ea_idct_put_c(dest_cr, frame->linesize[2], block[5]);
}
}
static inline void tgq_dconly(TgqContext *s, unsigned char *dst,
ptrdiff_t dst_stride, int dc)
{
int level = av_clip_uint8((dc*s->qtable[0] + 2056) >> 4);
int j;
for (j = 0; j < 8; j++)
memset(dst + j * dst_stride, level, 8);
}
static void tgq_idct_put_mb_dconly(TgqContext *s, AVFrame *frame,
int mb_x, int mb_y, const int8_t *dc)
{
ptrdiff_t linesize = frame->linesize[0];
uint8_t *dest_y = frame->data[0] + (mb_y * 16 * linesize) + mb_x * 16;
uint8_t *dest_cb = frame->data[1] + (mb_y * 8 * frame->linesize[1]) + mb_x * 8;
uint8_t *dest_cr = frame->data[2] + (mb_y * 8 * frame->linesize[2]) + mb_x * 8;
tgq_dconly(s, dest_y, linesize, dc[0]);
tgq_dconly(s, dest_y + 8, linesize, dc[1]);
tgq_dconly(s, dest_y + 8 * linesize, linesize, dc[2]);
tgq_dconly(s, dest_y + 8 * linesize + 8, linesize, dc[3]);
if (!(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {
tgq_dconly(s, dest_cb, frame->linesize[1], dc[4]);
tgq_dconly(s, dest_cr, frame->linesize[2], dc[5]);
}
}
static int tgq_decode_mb(TgqContext *s, AVFrame *frame, int mb_y, int mb_x)
{
int mode;
int i;
int8_t dc[6];
mode = bytestream2_get_byte(&s->gb);
if (mode > 12) {
GetBitContext gb;
int ret = init_get_bits8(&gb, s->gb.buffer, FFMIN(bytestream2_get_bytes_left(&s->gb), mode));
if (ret < 0)
return ret;
for (i = 0; i < 6; i++)
tgq_decode_block(s, s->block[i], &gb);
tgq_idct_put_mb(s, s->block, frame, mb_x, mb_y);
bytestream2_skip(&s->gb, mode);
} else {
if (mode == 3) {
memset(dc, bytestream2_get_byte(&s->gb), 4);
dc[4] = bytestream2_get_byte(&s->gb);
dc[5] = bytestream2_get_byte(&s->gb);
} else if (mode == 6) {
bytestream2_get_buffer(&s->gb, dc, 6);
} else if (mode == 12) {
for (i = 0; i < 6; i++) {
dc[i] = bytestream2_get_byte(&s->gb);
bytestream2_skip(&s->gb, 1);
}
} else {
av_log(s->avctx, AV_LOG_ERROR, "unsupported mb mode %i\n", mode);
return -1;
}
tgq_idct_put_mb_dconly(s, frame, mb_x, mb_y, dc);
}
return 0;
}
static void tgq_calculate_qtable(TgqContext *s, int quant)
{
int i, j;
const int a = (14 * (100 - quant)) / 100 + 1;
const int b = (11 * (100 - quant)) / 100 + 4;
for (j = 0; j < 8; j++)
for (i = 0; i < 8; i++)
s->qtable[j * 8 + i] = ((a * (j + i) / (7 + 7) + b) *
ff_inv_aanscales[j * 8 + i]) >> (14 - 4);
}
static int tgq_decode_frame(AVCodecContext *avctx, AVFrame *frame,
int *got_frame, AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
TgqContext *s = avctx->priv_data;
int x, y, ret;
int big_endian;
if (buf_size < 16) {
av_log(avctx, AV_LOG_WARNING, "truncated header\n");
return AVERROR_INVALIDDATA;
}
big_endian = AV_RL32(&buf[4]) > 0x000FFFFF;
bytestream2_init(&s->gb, buf + 8, buf_size - 8);
if (big_endian) {
s->width = bytestream2_get_be16u(&s->gb);
s->height = bytestream2_get_be16u(&s->gb);
} else {
s->width = bytestream2_get_le16u(&s->gb);
s->height = bytestream2_get_le16u(&s->gb);
}
ret = ff_set_dimensions(s->avctx, s->width, s->height);
if (ret < 0)
return ret;
tgq_calculate_qtable(s, bytestream2_get_byteu(&s->gb));
bytestream2_skip(&s->gb, 3);
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
return ret;
frame->key_frame = 1;
frame->pict_type = AV_PICTURE_TYPE_I;
for (y = 0; y < FFALIGN(avctx->height, 16) >> 4; y++)
for (x = 0; x < FFALIGN(avctx->width, 16) >> 4; x++)
if (tgq_decode_mb(s, frame, y, x) < 0)
return AVERROR_INVALIDDATA;
*got_frame = 1;
return avpkt->size;
}
const FFCodec ff_eatgq_decoder = {
.p.name = "eatgq",
.p.long_name = NULL_IF_CONFIG_SMALL("Electronic Arts TGQ video"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_TGQ,
.priv_data_size = sizeof(TgqContext),
.init = tgq_decode_init,
FF_CODEC_DECODE_CB(tgq_decode_frame),
.p.capabilities = AV_CODEC_CAP_DR1,
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
};