2 * Sony PlayStation MDEC (Motion DECoder)
3 * Copyright (c) 2003 Michael Niedermayer
5 * based upon code from Sebastian Jedruszkiewicz <elf@frogger.rules.pl>
7 * This file is part of FFmpeg.
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26 * Sony PlayStation MDEC (Motion DECoder)
27 * This is very similar to intra-only MPEG-1.
37 typedef struct MDECContext {
38 AVCodecContext *avctx;
40 BswapDSPContext bbdsp;
51 DECLARE_ALIGNED(32, int16_t, block)[6][64];
52 DECLARE_ALIGNED(16, uint16_t, quant_matrix)[64];
53 uint8_t *bitstream_buffer;
54 unsigned int bitstream_buffer_size;
55 int block_last_index[6];
58 //very similar to MPEG-1
59 static inline int mdec_decode_block_intra(MDECContext *a, int16_t *block, int n)
61 int level, diff, i, j, run;
63 RLTable *rl = &ff_rl_mpeg1;
64 uint8_t * const scantable = a->scantable.permutated;
65 const uint16_t *quant_matrix = a->quant_matrix;
66 const int qscale = a->qscale;
69 if (a->version == 2) {
70 block[0] = 2 * get_sbits(&a->gb, 10) + 1024;
72 component = (n <= 3 ? 0 : n - 4 + 1);
73 diff = decode_dc(&a->gb, component);
74 a->last_dc[component] += diff;
75 block[0] = a->last_dc[component] * (1 << 3);
80 OPEN_READER(re, &a->gb);
81 /* now quantify & encode AC coefficients */
83 UPDATE_CACHE(re, &a->gb);
84 GET_RL_VLC(level, run, re, &a->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
88 } else if (level != 0) {
91 av_log(a->avctx, AV_LOG_ERROR,
92 "ac-tex damaged at %d %d\n", a->mb_x, a->mb_y);
93 return AVERROR_INVALIDDATA;
96 level = (level * qscale * quant_matrix[j]) >> 3;
97 level = (level ^ SHOW_SBITS(re, &a->gb, 1)) - SHOW_SBITS(re, &a->gb, 1);
98 LAST_SKIP_BITS(re, &a->gb, 1);
101 run = SHOW_UBITS(re, &a->gb, 6)+1; LAST_SKIP_BITS(re, &a->gb, 6);
102 UPDATE_CACHE(re, &a->gb);
103 level = SHOW_SBITS(re, &a->gb, 10); SKIP_BITS(re, &a->gb, 10);
106 av_log(a->avctx, AV_LOG_ERROR,
107 "ac-tex damaged at %d %d\n", a->mb_x, a->mb_y);
108 return AVERROR_INVALIDDATA;
113 level = (level * (unsigned)qscale * quant_matrix[j]) >> 3;
114 level = (level - 1) | 1;
117 level = (level * (unsigned)qscale * quant_matrix[j]) >> 3;
118 level = (level - 1) | 1;
124 CLOSE_READER(re, &a->gb);
126 a->block_last_index[n] = i;
130 static inline int decode_mb(MDECContext *a, int16_t block[6][64])
133 static const int block_index[6] = { 5, 4, 0, 1, 2, 3 };
135 a->bdsp.clear_blocks(block[0]);
137 for (i = 0; i < 6; i++) {
138 if ((ret = mdec_decode_block_intra(a, block[block_index[i]],
139 block_index[i])) < 0)
141 if (get_bits_left(&a->gb) < 0)
142 return AVERROR_INVALIDDATA;
147 static inline void idct_put(MDECContext *a, AVFrame *frame, int mb_x, int mb_y)
149 int16_t (*block)[64] = a->block;
150 int linesize = frame->linesize[0];
152 uint8_t *dest_y = frame->data[0] + (mb_y * 16* linesize ) + mb_x * 16;
153 uint8_t *dest_cb = frame->data[1] + (mb_y * 8 * frame->linesize[1]) + mb_x * 8;
154 uint8_t *dest_cr = frame->data[2] + (mb_y * 8 * frame->linesize[2]) + mb_x * 8;
156 a->idsp.idct_put(dest_y, linesize, block[0]);
157 a->idsp.idct_put(dest_y + 8, linesize, block[1]);
158 a->idsp.idct_put(dest_y + 8 * linesize, linesize, block[2]);
159 a->idsp.idct_put(dest_y + 8 * linesize + 8, linesize, block[3]);
161 if (!(a->avctx->flags & AV_CODEC_FLAG_GRAY)) {
162 a->idsp.idct_put(dest_cb, frame->linesize[1], block[4]);
163 a->idsp.idct_put(dest_cr, frame->linesize[2], block[5]);
167 static int decode_frame(AVCodecContext *avctx,
168 void *data, int *got_frame,
171 MDECContext * const a = avctx->priv_data;
172 const uint8_t *buf = avpkt->data;
173 int buf_size = avpkt->size;
174 ThreadFrame frame = { .f = data };
177 if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0)
179 frame.f->pict_type = AV_PICTURE_TYPE_I;
180 frame.f->key_frame = 1;
182 av_fast_padded_malloc(&a->bitstream_buffer, &a->bitstream_buffer_size, buf_size);
183 if (!a->bitstream_buffer)
184 return AVERROR(ENOMEM);
185 a->bbdsp.bswap16_buf((uint16_t *)a->bitstream_buffer, (uint16_t *)buf, (buf_size + 1) / 2);
186 if ((ret = init_get_bits8(&a->gb, a->bitstream_buffer, buf_size)) < 0)
189 /* skip over 4 preamble bytes in stream (typically 0xXX 0xXX 0x00 0x38) */
190 skip_bits(&a->gb, 32);
192 a->qscale = get_bits(&a->gb, 16);
193 a->version = get_bits(&a->gb, 16);
195 a->last_dc[0] = a->last_dc[1] = a->last_dc[2] = 128;
197 for (a->mb_x = 0; a->mb_x < a->mb_width; a->mb_x++) {
198 for (a->mb_y = 0; a->mb_y < a->mb_height; a->mb_y++) {
199 if ((ret = decode_mb(a, a->block)) < 0)
202 idct_put(a, frame.f, a->mb_x, a->mb_y);
208 return (get_bits_count(&a->gb) + 31) / 32 * 4;
211 static av_cold int decode_init(AVCodecContext *avctx)
213 MDECContext * const a = avctx->priv_data;
216 a->mb_width = (avctx->coded_width + 15) / 16;
217 a->mb_height = (avctx->coded_height + 15) / 16;
221 ff_blockdsp_init(&a->bdsp, avctx);
222 ff_bswapdsp_init(&a->bbdsp);
223 ff_idctdsp_init(&a->idsp, avctx);
224 ff_mpeg12_init_vlcs();
225 ff_init_scantable(a->idsp.idct_permutation, &a->scantable,
228 avctx->pix_fmt = AV_PIX_FMT_YUVJ420P;
229 avctx->color_range = AVCOL_RANGE_JPEG;
232 for (i = 0; i < 64; i++) {
233 int j = a->idsp.idct_permutation[i];
235 a->quant_matrix[j] = ff_mpeg1_default_intra_matrix[i];
241 static av_cold int decode_end(AVCodecContext *avctx)
243 MDECContext * const a = avctx->priv_data;
245 av_freep(&a->bitstream_buffer);
246 a->bitstream_buffer_size = 0;
251 AVCodec ff_mdec_decoder = {
253 .long_name = NULL_IF_CONFIG_SMALL("Sony PlayStation MDEC (Motion DECoder)"),
254 .type = AVMEDIA_TYPE_VIDEO,
255 .id = AV_CODEC_ID_MDEC,
256 .priv_data_size = sizeof(MDECContext),
259 .decode = decode_frame,
260 .capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
261 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,