yading@10: /*
yading@10:  * Miro VideoXL codec
yading@10:  * Copyright (c) 2004 Konstantin Shishkov
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 Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: /**
yading@10:  * @file
yading@10:  * Miro VideoXL codec.
yading@10:  */
yading@10: 
yading@10: #include "libavutil/common.h"
yading@10: #include "libavutil/intreadwrite.h"
yading@10: #include "avcodec.h"
yading@10: #include "internal.h"
yading@10: 
yading@10: static const int xl_table[32] = {
yading@10:    0,   1,   2,   3,   4,   5,   6,   7,
yading@10:    8,   9,  12,  15,  20,  25,  34,  46,
yading@10:   64,  82,  94, 103, 108, 113, 116, 119,
yading@10:  120, 121, 122, 123, 124, 125, 126, 127
yading@10: };
yading@10: 
yading@10: static int 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:     AVFrame * const p = data;
yading@10:     uint8_t *Y, *U, *V;
yading@10:     int i, j, ret;
yading@10:     int stride;
yading@10:     uint32_t val;
yading@10:     int y0, y1, y2, y3 = 0, c0 = 0, c1 = 0;
yading@10: 
yading@10:     if (avctx->width & 3) {
yading@10:         av_log(avctx, AV_LOG_ERROR, "width is not a multiple of 4\n");
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10: 
yading@10:     if (buf_size < avctx->width * avctx->height) {
yading@10:         av_log(avctx, AV_LOG_ERROR, "Packet is too small\n");
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10: 
yading@10:     if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
yading@10:         return ret;
yading@10:     p->pict_type = AV_PICTURE_TYPE_I;
yading@10:     p->key_frame = 1;
yading@10: 
yading@10:     Y = p->data[0];
yading@10:     U = p->data[1];
yading@10:     V = p->data[2];
yading@10: 
yading@10:     stride = avctx->width - 4;
yading@10: 
yading@10:     for (i = 0; i < avctx->height; i++) {
yading@10:         /* lines are stored in reversed order */
yading@10:         buf += stride;
yading@10: 
yading@10:         for (j = 0; j < avctx->width; j += 4) {
yading@10:             /* value is stored in LE dword with word swapped */
yading@10:             val = AV_RL32(buf);
yading@10:             buf -= 4;
yading@10:             val = ((val >> 16) & 0xFFFF) | ((val & 0xFFFF) << 16);
yading@10: 
yading@10:             if(!j)
yading@10:                 y0 = (val & 0x1F) << 2;
yading@10:             else
yading@10:                 y0 = y3 + xl_table[val & 0x1F];
yading@10:             val >>= 5;
yading@10:             y1 = y0 + xl_table[val & 0x1F];
yading@10:             val >>= 5;
yading@10:             y2 = y1 + xl_table[val & 0x1F];
yading@10:             val >>= 6; /* align to word */
yading@10:             y3 = y2 + xl_table[val & 0x1F];
yading@10:             val >>= 5;
yading@10:             if(!j)
yading@10:                 c0 = (val & 0x1F) << 2;
yading@10:             else
yading@10:                 c0 += xl_table[val & 0x1F];
yading@10:             val >>= 5;
yading@10:             if(!j)
yading@10:                 c1 = (val & 0x1F) << 2;
yading@10:             else
yading@10:                 c1 += xl_table[val & 0x1F];
yading@10: 
yading@10:             Y[j + 0] = y0 << 1;
yading@10:             Y[j + 1] = y1 << 1;
yading@10:             Y[j + 2] = y2 << 1;
yading@10:             Y[j + 3] = y3 << 1;
yading@10: 
yading@10:             U[j >> 2] = c0 << 1;
yading@10:             V[j >> 2] = c1 << 1;
yading@10:         }
yading@10: 
yading@10:         buf += avctx->width + 4;
yading@10:         Y += p->linesize[0];
yading@10:         U += p->linesize[1];
yading@10:         V += p->linesize[2];
yading@10:     }
yading@10: 
yading@10:     *got_frame = 1;
yading@10: 
yading@10:     return buf_size;
yading@10: }
yading@10: 
yading@10: static av_cold int decode_init(AVCodecContext *avctx)
yading@10: {
yading@10:     avctx->pix_fmt = AV_PIX_FMT_YUV411P;
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: AVCodec ff_xl_decoder = {
yading@10:     .name           = "xl",
yading@10:     .type           = AVMEDIA_TYPE_VIDEO,
yading@10:     .id             = AV_CODEC_ID_VIXL,
yading@10:     .init           = decode_init,
yading@10:     .decode         = decode_frame,
yading@10:     .capabilities   = CODEC_CAP_DR1,
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("Miro VideoXL"),
yading@10: };