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 Libav.
9 * Libav 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 * Libav 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 Libav; 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.
36 typedef struct MDECContext {
37 AVCodecContext *avctx;
49 DECLARE_ALIGNED(16, int16_t, block)[6][64];
50 uint8_t *bitstream_buffer;
51 unsigned int bitstream_buffer_size;
52 int block_last_index[6];
55 //very similar to MPEG-1
56 static inline int mdec_decode_block_intra(MDECContext *a, int16_t *block, int n)
58 int level, diff, i, j, run;
60 RLTable *rl = &ff_rl_mpeg1;
61 uint8_t * const scantable = a->scantable.permutated;
62 const uint16_t *quant_matrix = ff_mpeg1_default_intra_matrix;
63 const int qscale = a->qscale;
66 if (a->version == 2) {
67 block[0] = 2 * get_sbits(&a->gb, 10) + 1024;
69 component = (n <= 3 ? 0 : n - 4 + 1);
70 diff = decode_dc(&a->gb, component);
72 return AVERROR_INVALIDDATA;
73 a->last_dc[component] += diff;
74 block[0] = a->last_dc[component] << 3;
79 OPEN_READER(re, &a->gb);
80 /* now quantify & encode AC coefficients */
82 UPDATE_CACHE(re, &a->gb);
83 GET_RL_VLC(level, run, re, &a->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
87 } else if (level != 0) {
90 av_log(a->avctx, AV_LOG_ERROR,
91 "ac-tex damaged at %d %d\n", a->mb_x, a->mb_y);
92 return AVERROR_INVALIDDATA;
95 level = (level * qscale * quant_matrix[j]) >> 3;
96 level = (level ^ SHOW_SBITS(re, &a->gb, 1)) - SHOW_SBITS(re, &a->gb, 1);
97 LAST_SKIP_BITS(re, &a->gb, 1);
100 run = SHOW_UBITS(re, &a->gb, 6)+1; LAST_SKIP_BITS(re, &a->gb, 6);
101 UPDATE_CACHE(re, &a->gb);
102 level = SHOW_SBITS(re, &a->gb, 10); SKIP_BITS(re, &a->gb, 10);
105 av_log(a->avctx, AV_LOG_ERROR,
106 "ac-tex damaged at %d %d\n", a->mb_x, a->mb_y);
107 return AVERROR_INVALIDDATA;
112 level = (level * qscale * quant_matrix[j]) >> 3;
113 level = (level - 1) | 1;
116 level = (level * qscale * quant_matrix[j]) >> 3;
117 level = (level - 1) | 1;
123 CLOSE_READER(re, &a->gb);
125 a->block_last_index[n] = i;
129 static inline int decode_mb(MDECContext *a, int16_t block[6][64])
132 static const int block_index[6] = { 5, 4, 0, 1, 2, 3 };
134 a->bdsp.clear_blocks(block[0]);
136 for (i = 0; i < 6; i++) {
137 if ((ret = mdec_decode_block_intra(a, block[block_index[i]],
138 block_index[i])) < 0)
140 if (get_bits_left(&a->gb) < 0)
141 return AVERROR_INVALIDDATA;
146 static inline void idct_put(MDECContext *a, AVFrame *frame, int mb_x, int mb_y)
148 int16_t (*block)[64] = a->block;
149 int linesize = frame->linesize[0];
151 uint8_t *dest_y = frame->data[0] + (mb_y * 16* linesize ) + mb_x * 16;
152 uint8_t *dest_cb = frame->data[1] + (mb_y * 8 * frame->linesize[1]) + mb_x * 8;
153 uint8_t *dest_cr = frame->data[2] + (mb_y * 8 * frame->linesize[2]) + mb_x * 8;
155 a->idsp.idct_put(dest_y, linesize, block[0]);
156 a->idsp.idct_put(dest_y + 8, linesize, block[1]);
157 a->idsp.idct_put(dest_y + 8 * linesize, linesize, block[2]);
158 a->idsp.idct_put(dest_y + 8 * linesize + 8, linesize, block[3]);
160 if (!(a->avctx->flags & AV_CODEC_FLAG_GRAY)) {
161 a->idsp.idct_put(dest_cb, frame->linesize[1], block[4]);
162 a->idsp.idct_put(dest_cr, frame->linesize[2], block[5]);
166 static int decode_frame(AVCodecContext *avctx,
167 void *data, int *got_frame,
170 MDECContext * const a = avctx->priv_data;
171 const uint8_t *buf = avpkt->data;
172 int buf_size = avpkt->size;
173 ThreadFrame frame = { .f = data };
176 if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0) {
177 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
180 frame.f->pict_type = AV_PICTURE_TYPE_I;
181 frame.f->key_frame = 1;
183 av_fast_malloc(&a->bitstream_buffer, &a->bitstream_buffer_size, buf_size + AV_INPUT_BUFFER_PADDING_SIZE);
184 if (!a->bitstream_buffer)
185 return AVERROR(ENOMEM);
186 for (i = 0; i < buf_size; i += 2) {
187 a->bitstream_buffer[i] = buf[i + 1];
188 a->bitstream_buffer[i + 1] = buf[i];
190 init_get_bits(&a->gb, a->bitstream_buffer, buf_size * 8);
192 /* skip over 4 preamble bytes in stream (typically 0xXX 0xXX 0x00 0x38) */
193 skip_bits(&a->gb, 32);
195 a->qscale = get_bits(&a->gb, 16);
196 a->version = get_bits(&a->gb, 16);
198 a->last_dc[0] = a->last_dc[1] = a->last_dc[2] = 128;
200 for (a->mb_x = 0; a->mb_x < a->mb_width; a->mb_x++) {
201 for (a->mb_y = 0; a->mb_y < a->mb_height; a->mb_y++) {
202 if ((ret = decode_mb(a, a->block)) < 0)
205 idct_put(a, frame.f, a->mb_x, a->mb_y);
211 return (get_bits_count(&a->gb) + 31) / 32 * 4;
214 static av_cold int decode_init(AVCodecContext *avctx)
216 MDECContext * const a = avctx->priv_data;
218 a->mb_width = (avctx->coded_width + 15) / 16;
219 a->mb_height = (avctx->coded_height + 15) / 16;
223 ff_blockdsp_init(&a->bdsp);
224 ff_idctdsp_init(&a->idsp, avctx);
225 ff_mpeg12_init_vlcs();
226 ff_init_scantable(a->idsp.idct_permutation, &a->scantable,
229 if (avctx->idct_algo == FF_IDCT_AUTO)
230 avctx->idct_algo = FF_IDCT_SIMPLE;
231 avctx->pix_fmt = AV_PIX_FMT_YUVJ420P;
232 avctx->color_range = AVCOL_RANGE_JPEG;
237 static av_cold int decode_init_thread_copy(AVCodecContext *avctx)
239 MDECContext * const a = avctx->priv_data;
246 static av_cold int decode_end(AVCodecContext *avctx)
248 MDECContext * const a = avctx->priv_data;
250 av_freep(&a->bitstream_buffer);
251 a->bitstream_buffer_size = 0;
256 AVCodec ff_mdec_decoder = {
258 .long_name = NULL_IF_CONFIG_SMALL("Sony PlayStation MDEC (Motion DECoder)"),
259 .type = AVMEDIA_TYPE_VIDEO,
260 .id = AV_CODEC_ID_MDEC,
261 .priv_data_size = sizeof(MDECContext),
264 .decode = decode_frame,
265 .capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
266 .init_thread_copy = ONLY_IF_THREADS_ENABLED(decode_init_thread_copy)