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1 /*
2  * Electronic Arts TGQ Video Decoder
3  * Copyright (c) 2007-2008 Peter Ross <pross@xvid.org>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
20  */
21 
22 /**
23  * @file
24  * Electronic Arts TGQ Video Decoder
25  * @author Peter Ross <pross@xvid.org>
26  *
27  * Technical details here:
28  * http://wiki.multimedia.cx/index.php?title=Electronic_Arts_TGQ
29  */
30 
31 #define BITSTREAM_READER_LE
32 
33 #include "libavutil/mem_internal.h"
34 
35 #include "aandcttab.h"
36 #include "avcodec.h"
37 #include "bytestream.h"
38 #include "eaidct.h"
39 #include "get_bits.h"
40 #include "idctdsp.h"
41 #include "internal.h"
42 
43 typedef struct TgqContext {
44     AVCodecContext *avctx;
45     int width, height;
46     ScanTable scantable;
47     int qtable[64];
48     DECLARE_ALIGNED(16, int16_t, block)[6][64];
49     GetByteContext gb;
50 } TgqContext;
51 
tgq_decode_init(AVCodecContext * avctx)52 static av_cold int tgq_decode_init(AVCodecContext *avctx)
53 {
54     TgqContext *s = avctx->priv_data;
55     uint8_t idct_permutation[64];
56     s->avctx = avctx;
57     ff_init_scantable_permutation(idct_permutation, FF_IDCT_PERM_NONE);
58     ff_init_scantable(idct_permutation, &s->scantable, ff_zigzag_direct);
59     avctx->framerate = (AVRational){ 15, 1 };
60     avctx->pix_fmt   = AV_PIX_FMT_YUV420P;
61     return 0;
62 }
63 
tgq_decode_block(TgqContext * s,int16_t block[64],GetBitContext * gb)64 static void tgq_decode_block(TgqContext *s, int16_t block[64], GetBitContext *gb)
65 {
66     uint8_t *perm = s->scantable.permutated;
67     int i, j, value;
68     block[0] = get_sbits(gb, 8) * s->qtable[0];
69     for (i = 1; i < 64;) {
70         switch (show_bits(gb, 3)) {
71         case 4:
72             block[perm[i++]] = 0;
73         case 0:
74             block[perm[i++]] = 0;
75             skip_bits(gb, 3);
76             break;
77         case 5:
78         case 1:
79             skip_bits(gb, 2);
80             value = get_bits(gb, 6);
81             for (j = 0; j < value; j++)
82                 block[perm[i++]] = 0;
83             break;
84         case 6:
85             skip_bits(gb, 3);
86             block[perm[i]] = -s->qtable[perm[i]];
87             i++;
88             break;
89         case 2:
90             skip_bits(gb, 3);
91             block[perm[i]] = s->qtable[perm[i]];
92             i++;
93             break;
94         case 7: // 111b
95         case 3: // 011b
96             skip_bits(gb, 2);
97             if (show_bits(gb, 6) == 0x3F) {
98                 skip_bits(gb, 6);
99                 block[perm[i]] = get_sbits(gb, 8) * s->qtable[perm[i]];
100             } else {
101                 block[perm[i]] = get_sbits(gb, 6) * s->qtable[perm[i]];
102             }
103             i++;
104             break;
105         }
106     }
107     block[0] += 128 << 4;
108 }
109 
tgq_idct_put_mb(TgqContext * s,int16_t (* block)[64],AVFrame * frame,int mb_x,int mb_y)110 static void tgq_idct_put_mb(TgqContext *s, int16_t (*block)[64], AVFrame *frame,
111                             int mb_x, int mb_y)
112 {
113     ptrdiff_t linesize = frame->linesize[0];
114     uint8_t *dest_y  = frame->data[0] + (mb_y * 16 * linesize)           + mb_x * 16;
115     uint8_t *dest_cb = frame->data[1] + (mb_y * 8  * frame->linesize[1]) + mb_x * 8;
116     uint8_t *dest_cr = frame->data[2] + (mb_y * 8  * frame->linesize[2]) + mb_x * 8;
117 
118     ff_ea_idct_put_c(dest_y                   , linesize, block[0]);
119     ff_ea_idct_put_c(dest_y                + 8, linesize, block[1]);
120     ff_ea_idct_put_c(dest_y + 8 * linesize    , linesize, block[2]);
121     ff_ea_idct_put_c(dest_y + 8 * linesize + 8, linesize, block[3]);
122     if (!(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {
123          ff_ea_idct_put_c(dest_cb, frame->linesize[1], block[4]);
124          ff_ea_idct_put_c(dest_cr, frame->linesize[2], block[5]);
125     }
126 }
127 
tgq_dconly(TgqContext * s,unsigned char * dst,ptrdiff_t dst_stride,int dc)128 static inline void tgq_dconly(TgqContext *s, unsigned char *dst,
129                               ptrdiff_t dst_stride, int dc)
130 {
131     int level = av_clip_uint8((dc*s->qtable[0] + 2056) >> 4);
132     int j;
133     for (j = 0; j < 8; j++)
134         memset(dst + j * dst_stride, level, 8);
135 }
136 
tgq_idct_put_mb_dconly(TgqContext * s,AVFrame * frame,int mb_x,int mb_y,const int8_t * dc)137 static void tgq_idct_put_mb_dconly(TgqContext *s, AVFrame *frame,
138                                    int mb_x, int mb_y, const int8_t *dc)
139 {
140     ptrdiff_t linesize = frame->linesize[0];
141     uint8_t *dest_y  = frame->data[0] + (mb_y * 16 * linesize)             + mb_x * 16;
142     uint8_t *dest_cb = frame->data[1] + (mb_y * 8  * frame->linesize[1]) + mb_x * 8;
143     uint8_t *dest_cr = frame->data[2] + (mb_y * 8  * frame->linesize[2]) + mb_x * 8;
144     tgq_dconly(s, dest_y,                    linesize, dc[0]);
145     tgq_dconly(s, dest_y                + 8, linesize, dc[1]);
146     tgq_dconly(s, dest_y + 8 * linesize,     linesize, dc[2]);
147     tgq_dconly(s, dest_y + 8 * linesize + 8, linesize, dc[3]);
148     if (!(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {
149         tgq_dconly(s, dest_cb, frame->linesize[1], dc[4]);
150         tgq_dconly(s, dest_cr, frame->linesize[2], dc[5]);
151     }
152 }
153 
tgq_decode_mb(TgqContext * s,AVFrame * frame,int mb_y,int mb_x)154 static int tgq_decode_mb(TgqContext *s, AVFrame *frame, int mb_y, int mb_x)
155 {
156     int mode;
157     int i;
158     int8_t dc[6];
159 
160     mode = bytestream2_get_byte(&s->gb);
161     if (mode > 12) {
162         GetBitContext gb;
163         int ret = init_get_bits8(&gb, s->gb.buffer, FFMIN(bytestream2_get_bytes_left(&s->gb), mode));
164         if (ret < 0)
165             return ret;
166 
167         for (i = 0; i < 6; i++)
168             tgq_decode_block(s, s->block[i], &gb);
169         tgq_idct_put_mb(s, s->block, frame, mb_x, mb_y);
170         bytestream2_skip(&s->gb, mode);
171     } else {
172         if (mode == 3) {
173             memset(dc, bytestream2_get_byte(&s->gb), 4);
174             dc[4] = bytestream2_get_byte(&s->gb);
175             dc[5] = bytestream2_get_byte(&s->gb);
176         } else if (mode == 6) {
177             bytestream2_get_buffer(&s->gb, dc, 6);
178         } else if (mode == 12) {
179             for (i = 0; i < 6; i++) {
180                 dc[i] = bytestream2_get_byte(&s->gb);
181                 bytestream2_skip(&s->gb, 1);
182             }
183         } else {
184             av_log(s->avctx, AV_LOG_ERROR, "unsupported mb mode %i\n", mode);
185             return -1;
186         }
187         tgq_idct_put_mb_dconly(s, frame, mb_x, mb_y, dc);
188     }
189     return 0;
190 }
191 
tgq_calculate_qtable(TgqContext * s,int quant)192 static void tgq_calculate_qtable(TgqContext *s, int quant)
193 {
194     int i, j;
195     const int a = (14 * (100 - quant)) / 100 + 1;
196     const int b = (11 * (100 - quant)) / 100 + 4;
197     for (j = 0; j < 8; j++)
198         for (i = 0; i < 8; i++)
199             s->qtable[j * 8 + i] = ((a * (j + i) / (7 + 7) + b) *
200                                     ff_inv_aanscales[j * 8 + i]) >> (14 - 4);
201 }
202 
tgq_decode_frame(AVCodecContext * avctx,void * data,int * got_frame,AVPacket * avpkt)203 static int tgq_decode_frame(AVCodecContext *avctx,
204                             void *data, int *got_frame,
205                             AVPacket *avpkt)
206 {
207     const uint8_t *buf = avpkt->data;
208     int buf_size       = avpkt->size;
209     TgqContext *s      = avctx->priv_data;
210     AVFrame *frame     = data;
211     int x, y, ret;
212     int big_endian;
213 
214     if (buf_size < 16) {
215         av_log(avctx, AV_LOG_WARNING, "truncated header\n");
216         return AVERROR_INVALIDDATA;
217     }
218     big_endian = AV_RL32(&buf[4]) > 0x000FFFFF;
219     bytestream2_init(&s->gb, buf + 8, buf_size - 8);
220     if (big_endian) {
221         s->width  = bytestream2_get_be16u(&s->gb);
222         s->height = bytestream2_get_be16u(&s->gb);
223     } else {
224         s->width  = bytestream2_get_le16u(&s->gb);
225         s->height = bytestream2_get_le16u(&s->gb);
226     }
227 
228     ret = ff_set_dimensions(s->avctx, s->width, s->height);
229     if (ret < 0)
230         return ret;
231 
232     tgq_calculate_qtable(s, bytestream2_get_byteu(&s->gb));
233     bytestream2_skip(&s->gb, 3);
234 
235     if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
236         return ret;
237     frame->key_frame = 1;
238     frame->pict_type = AV_PICTURE_TYPE_I;
239 
240     for (y = 0; y < FFALIGN(avctx->height, 16) >> 4; y++)
241         for (x = 0; x < FFALIGN(avctx->width, 16) >> 4; x++)
242             if (tgq_decode_mb(s, frame, y, x) < 0)
243                 return AVERROR_INVALIDDATA;
244 
245     *got_frame = 1;
246 
247     return avpkt->size;
248 }
249 
250 AVCodec ff_eatgq_decoder = {
251     .name           = "eatgq",
252     .long_name      = NULL_IF_CONFIG_SMALL("Electronic Arts TGQ video"),
253     .type           = AVMEDIA_TYPE_VIDEO,
254     .id             = AV_CODEC_ID_TGQ,
255     .priv_data_size = sizeof(TgqContext),
256     .init           = tgq_decode_init,
257     .decode         = tgq_decode_frame,
258     .capabilities   = AV_CODEC_CAP_DR1,
259 };
260