yading@10: /*
yading@10:  * Electronic Arts TGQ Video Decoder
yading@10:  * Copyright (c) 2007-2008 Peter Ross <pross@xvid.org>
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
yading@10:  */
yading@10: 
yading@10: /**
yading@10:  * @file
yading@10:  * Electronic Arts TGQ Video Decoder
yading@10:  * @author Peter Ross <pross@xvid.org>
yading@10:  *
yading@10:  * Technical details here:
yading@10:  * http://wiki.multimedia.cx/index.php?title=Electronic_Arts_TGQ
yading@10:  */
yading@10: 
yading@10: #include "avcodec.h"
yading@10: #define BITSTREAM_READER_LE
yading@10: #include "get_bits.h"
yading@10: #include "bytestream.h"
yading@10: #include "dsputil.h"
yading@10: #include "aandcttab.h"
yading@10: #include "eaidct.h"
yading@10: #include "internal.h"
yading@10: 
yading@10: typedef struct TgqContext {
yading@10:     AVCodecContext *avctx;
yading@10:     int width, height;
yading@10:     ScanTable scantable;
yading@10:     int qtable[64];
yading@10:     DECLARE_ALIGNED(16, int16_t, block)[6][64];
yading@10:     GetByteContext gb;
yading@10: } TgqContext;
yading@10: 
yading@10: static av_cold int tgq_decode_init(AVCodecContext *avctx)
yading@10: {
yading@10:     TgqContext *s = avctx->priv_data;
yading@10:     uint8_t idct_permutation[64];
yading@10:     s->avctx = avctx;
yading@10:     ff_init_scantable_permutation(idct_permutation, FF_NO_IDCT_PERM);
yading@10:     ff_init_scantable(idct_permutation, &s->scantable, ff_zigzag_direct);
yading@10:     avctx->time_base = (AVRational){1, 15};
yading@10:     avctx->pix_fmt   = AV_PIX_FMT_YUV420P;
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static void tgq_decode_block(TgqContext *s, int16_t block[64], GetBitContext *gb)
yading@10: {
yading@10:     uint8_t *perm = s->scantable.permutated;
yading@10:     int i, j, value;
yading@10:     block[0] = get_sbits(gb, 8) * s->qtable[0];
yading@10:     for (i = 1; i < 64;) {
yading@10:         switch (show_bits(gb, 3)) {
yading@10:         case 4:
yading@10:             block[perm[i++]] = 0;
yading@10:         case 0:
yading@10:             block[perm[i++]] = 0;
yading@10:             skip_bits(gb, 3);
yading@10:             break;
yading@10:         case 5:
yading@10:         case 1:
yading@10:             skip_bits(gb, 2);
yading@10:             value = get_bits(gb, 6);
yading@10:             for (j = 0; j < value; j++)
yading@10:                 block[perm[i++]] = 0;
yading@10:             break;
yading@10:         case 6:
yading@10:             skip_bits(gb, 3);
yading@10:             block[perm[i]] = -s->qtable[perm[i]];
yading@10:             i++;
yading@10:             break;
yading@10:         case 2:
yading@10:             skip_bits(gb, 3);
yading@10:             block[perm[i]] = s->qtable[perm[i]];
yading@10:             i++;
yading@10:             break;
yading@10:         case 7: // 111b
yading@10:         case 3: // 011b
yading@10:             skip_bits(gb, 2);
yading@10:             if (show_bits(gb, 6) == 0x3F) {
yading@10:                 skip_bits(gb, 6);
yading@10:                 block[perm[i]] = get_sbits(gb, 8) * s->qtable[perm[i]];
yading@10:             } else {
yading@10:                 block[perm[i]] = get_sbits(gb, 6) * s->qtable[perm[i]];
yading@10:             }
yading@10:             i++;
yading@10:             break;
yading@10:         }
yading@10:     }
yading@10:     block[0] += 128 << 4;
yading@10: }
yading@10: 
yading@10: static void tgq_idct_put_mb(TgqContext *s, int16_t (*block)[64], AVFrame *frame,
yading@10:                             int mb_x, int mb_y)
yading@10: {
yading@10:     int linesize = frame->linesize[0];
yading@10:     uint8_t *dest_y  = frame->data[0] + (mb_y * 16 * linesize)           + mb_x * 16;
yading@10:     uint8_t *dest_cb = frame->data[1] + (mb_y * 8  * frame->linesize[1]) + mb_x * 8;
yading@10:     uint8_t *dest_cr = frame->data[2] + (mb_y * 8  * frame->linesize[2]) + mb_x * 8;
yading@10: 
yading@10:     ff_ea_idct_put_c(dest_y                   , linesize, block[0]);
yading@10:     ff_ea_idct_put_c(dest_y                + 8, linesize, block[1]);
yading@10:     ff_ea_idct_put_c(dest_y + 8 * linesize    , linesize, block[2]);
yading@10:     ff_ea_idct_put_c(dest_y + 8 * linesize + 8, linesize, block[3]);
yading@10:     if (!(s->avctx->flags & CODEC_FLAG_GRAY)) {
yading@10:          ff_ea_idct_put_c(dest_cb, frame->linesize[1], block[4]);
yading@10:          ff_ea_idct_put_c(dest_cr, frame->linesize[2], block[5]);
yading@10:     }
yading@10: }
yading@10: 
yading@10: static inline void tgq_dconly(TgqContext *s, unsigned char *dst,
yading@10:                               int dst_stride, int dc)
yading@10: {
yading@10:     int level = av_clip_uint8((dc*s->qtable[0] + 2056) >> 4);
yading@10:     int j;
yading@10:     for (j = 0; j < 8; j++)
yading@10:         memset(dst + j * dst_stride, level, 8);
yading@10: }
yading@10: 
yading@10: static void tgq_idct_put_mb_dconly(TgqContext *s, AVFrame *frame,
yading@10:                                    int mb_x, int mb_y, const int8_t *dc)
yading@10: {
yading@10:     int linesize = frame->linesize[0];
yading@10:     uint8_t *dest_y  = frame->data[0] + (mb_y * 16 * linesize)             + mb_x * 16;
yading@10:     uint8_t *dest_cb = frame->data[1] + (mb_y * 8  * frame->linesize[1]) + mb_x * 8;
yading@10:     uint8_t *dest_cr = frame->data[2] + (mb_y * 8  * frame->linesize[2]) + mb_x * 8;
yading@10:     tgq_dconly(s, dest_y,                    linesize, dc[0]);
yading@10:     tgq_dconly(s, dest_y                + 8, linesize, dc[1]);
yading@10:     tgq_dconly(s, dest_y + 8 * linesize,     linesize, dc[2]);
yading@10:     tgq_dconly(s, dest_y + 8 * linesize + 8, linesize, dc[3]);
yading@10:     if (!(s->avctx->flags & CODEC_FLAG_GRAY)) {
yading@10:         tgq_dconly(s, dest_cb, frame->linesize[1], dc[4]);
yading@10:         tgq_dconly(s, dest_cr, frame->linesize[2], dc[5]);
yading@10:     }
yading@10: }
yading@10: 
yading@10: static int tgq_decode_mb(TgqContext *s, AVFrame *frame, int mb_y, int mb_x)
yading@10: {
yading@10:     int mode;
yading@10:     int i;
yading@10:     int8_t dc[6];
yading@10: 
yading@10:     mode = bytestream2_get_byte(&s->gb);
yading@10:     if (mode > 12) {
yading@10:         GetBitContext gb;
yading@10:         init_get_bits(&gb, s->gb.buffer, FFMIN(bytestream2_get_bytes_left(&s->gb), mode) * 8);
yading@10:         for (i = 0; i < 6; i++)
yading@10:             tgq_decode_block(s, s->block[i], &gb);
yading@10:         tgq_idct_put_mb(s, s->block, frame, mb_x, mb_y);
yading@10:         bytestream2_skip(&s->gb, mode);
yading@10:     } else {
yading@10:         if (mode == 3) {
yading@10:             memset(dc, bytestream2_get_byte(&s->gb), 4);
yading@10:             dc[4] = bytestream2_get_byte(&s->gb);
yading@10:             dc[5] = bytestream2_get_byte(&s->gb);
yading@10:         } else if (mode == 6) {
yading@10:             bytestream2_get_buffer(&s->gb, dc, 6);
yading@10:         } else if (mode == 12) {
yading@10:             for (i = 0; i < 6; i++) {
yading@10:                 dc[i] = bytestream2_get_byte(&s->gb);
yading@10:                 bytestream2_skip(&s->gb, 1);
yading@10:             }
yading@10:         } else {
yading@10:             av_log(s->avctx, AV_LOG_ERROR, "unsupported mb mode %i\n", mode);
yading@10:             return -1;
yading@10:         }
yading@10:         tgq_idct_put_mb_dconly(s, frame, mb_x, mb_y, dc);
yading@10:     }
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static void tgq_calculate_qtable(TgqContext *s, int quant)
yading@10: {
yading@10:     int i, j;
yading@10:     const int a = (14 * (100 - quant)) / 100 + 1;
yading@10:     const int b = (11 * (100 - quant)) / 100 + 4;
yading@10:     for (j = 0; j < 8; j++)
yading@10:         for (i = 0; i < 8; i++)
yading@10:             s->qtable[j * 8 + i] = ((a * (j + i) / (7 + 7) + b) *
yading@10:                                     ff_inv_aanscales[j * 8 + i]) >> (14 - 4);
yading@10: }
yading@10: 
yading@10: static int tgq_decode_frame(AVCodecContext *avctx,
yading@10:                             void *data, int *got_frame,
yading@10:                             AVPacket *avpkt)
yading@10: {
yading@10:     const uint8_t *buf = avpkt->data;
yading@10:     int buf_size       = avpkt->size;
yading@10:     TgqContext *s      = avctx->priv_data;
yading@10:     AVFrame *frame     = data;
yading@10:     int x, y, ret;
yading@10:     int big_endian;
yading@10: 
yading@10:     if (buf_size < 16) {
yading@10:         av_log(avctx, AV_LOG_WARNING, "truncated header\n");
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10:     big_endian = AV_RL32(&buf[4]) > 0x000FFFFF;
yading@10:     bytestream2_init(&s->gb, buf + 8, buf_size - 8);
yading@10:     if (big_endian) {
yading@10:         s->width  = bytestream2_get_be16u(&s->gb);
yading@10:         s->height = bytestream2_get_be16u(&s->gb);
yading@10:     } else {
yading@10:         s->width  = bytestream2_get_le16u(&s->gb);
yading@10:         s->height = bytestream2_get_le16u(&s->gb);
yading@10:     }
yading@10: 
yading@10:     if (s->avctx->width!=s->width || s->avctx->height!=s->height) {
yading@10:         avcodec_set_dimensions(s->avctx, s->width, s->height);
yading@10:     }
yading@10:     tgq_calculate_qtable(s, bytestream2_get_byteu(&s->gb));
yading@10:     bytestream2_skip(&s->gb, 3);
yading@10: 
yading@10:     if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
yading@10:         return ret;
yading@10:     frame->key_frame = 1;
yading@10:     frame->pict_type = AV_PICTURE_TYPE_I;
yading@10: 
yading@10:     for (y = 0; y < FFALIGN(avctx->height, 16) >> 4; y++)
yading@10:         for (x = 0; x < FFALIGN(avctx->width, 16) >> 4; x++)
yading@10:             if (tgq_decode_mb(s, frame, y, x) < 0)
yading@10:                 return AVERROR_INVALIDDATA;
yading@10: 
yading@10:     *got_frame = 1;
yading@10: 
yading@10:     return avpkt->size;
yading@10: }
yading@10: 
yading@10: AVCodec ff_eatgq_decoder = {
yading@10:     .name           = "eatgq",
yading@10:     .type           = AVMEDIA_TYPE_VIDEO,
yading@10:     .id             = AV_CODEC_ID_TGQ,
yading@10:     .priv_data_size = sizeof(TgqContext),
yading@10:     .init           = tgq_decode_init,
yading@10:     .decode         = tgq_decode_frame,
yading@10:     .capabilities   = CODEC_CAP_DR1,
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("Electronic Arts TGQ video"),
yading@10: };