yading@10: /*
yading@10:  * Sony PlayStation MDEC (Motion DECoder)
yading@10:  * Copyright (c) 2003 Michael Niedermayer
yading@10:  *
yading@10:  * based upon code from Sebastian Jedruszkiewicz <elf@frogger.rules.pl>
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:  * Sony PlayStation MDEC (Motion DECoder)
yading@10:  * This is very similar to intra-only MPEG-1.
yading@10:  */
yading@10: 
yading@10: #include "avcodec.h"
yading@10: #include "mpegvideo.h"
yading@10: #include "mpeg12.h"
yading@10: #include "thread.h"
yading@10: 
yading@10: typedef struct MDECContext {
yading@10:     AVCodecContext *avctx;
yading@10:     DSPContext dsp;
yading@10:     ThreadFrame frame;
yading@10:     GetBitContext gb;
yading@10:     ScanTable scantable;
yading@10:     int version;
yading@10:     int qscale;
yading@10:     int last_dc[3];
yading@10:     int mb_width;
yading@10:     int mb_height;
yading@10:     int mb_x, mb_y;
yading@10:     DECLARE_ALIGNED(16, int16_t, block)[6][64];
yading@10:     uint8_t *bitstream_buffer;
yading@10:     unsigned int bitstream_buffer_size;
yading@10:     int block_last_index[6];
yading@10: } MDECContext;
yading@10: 
yading@10: //very similar to MPEG-1
yading@10: static inline int mdec_decode_block_intra(MDECContext *a, int16_t *block, int n)
yading@10: {
yading@10:     int level, diff, i, j, run;
yading@10:     int component;
yading@10:     RLTable *rl = &ff_rl_mpeg1;
yading@10:     uint8_t * const scantable = a->scantable.permutated;
yading@10:     const uint16_t *quant_matrix = ff_mpeg1_default_intra_matrix;
yading@10:     const int qscale = a->qscale;
yading@10: 
yading@10:     /* DC coefficient */
yading@10:     if (a->version == 2) {
yading@10:         block[0] = 2 * get_sbits(&a->gb, 10) + 1024;
yading@10:     } else {
yading@10:         component = (n <= 3 ? 0 : n - 4 + 1);
yading@10:         diff = decode_dc(&a->gb, component);
yading@10:         if (diff >= 0xffff)
yading@10:             return AVERROR_INVALIDDATA;
yading@10:         a->last_dc[component] += diff;
yading@10:         block[0] = a->last_dc[component] << 3;
yading@10:     }
yading@10: 
yading@10:     i = 0;
yading@10:     {
yading@10:         OPEN_READER(re, &a->gb);
yading@10:         /* now quantify & encode AC coefficients */
yading@10:         for (;;) {
yading@10:             UPDATE_CACHE(re, &a->gb);
yading@10:             GET_RL_VLC(level, run, re, &a->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
yading@10: 
yading@10:             if (level == 127) {
yading@10:                 break;
yading@10:             } else if (level != 0) {
yading@10:                 i    += run;
yading@10:                 j     = scantable[i];
yading@10:                 level = (level * qscale * quant_matrix[j]) >> 3;
yading@10:                 level = (level ^ SHOW_SBITS(re, &a->gb, 1)) - SHOW_SBITS(re, &a->gb, 1);
yading@10:                 LAST_SKIP_BITS(re, &a->gb, 1);
yading@10:             } else {
yading@10:                 /* escape */
yading@10:                 run = SHOW_UBITS(re, &a->gb, 6)+1; LAST_SKIP_BITS(re, &a->gb, 6);
yading@10:                 UPDATE_CACHE(re, &a->gb);
yading@10:                 level = SHOW_SBITS(re, &a->gb, 10); SKIP_BITS(re, &a->gb, 10);
yading@10:                 i    += run;
yading@10:                 j     = scantable[i];
yading@10:                 if (level < 0) {
yading@10:                     level = -level;
yading@10:                     level = (level * qscale * quant_matrix[j]) >> 3;
yading@10:                     level = (level - 1) | 1;
yading@10:                     level = -level;
yading@10:                 } else {
yading@10:                     level = (level * qscale * quant_matrix[j]) >> 3;
yading@10:                     level = (level - 1) | 1;
yading@10:                 }
yading@10:             }
yading@10:             if (i > 63) {
yading@10:                 av_log(a->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", a->mb_x, a->mb_y);
yading@10:                 return AVERROR_INVALIDDATA;
yading@10:             }
yading@10: 
yading@10:             block[j] = level;
yading@10:         }
yading@10:         CLOSE_READER(re, &a->gb);
yading@10:     }
yading@10:     a->block_last_index[n] = i;
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static inline int decode_mb(MDECContext *a, int16_t block[6][64])
yading@10: {
yading@10:     int i, ret;
yading@10:     const int block_index[6] = { 5, 4, 0, 1, 2, 3 };
yading@10: 
yading@10:     a->dsp.clear_blocks(block[0]);
yading@10: 
yading@10:     for (i = 0; i < 6; i++) {
yading@10:         if ((ret = mdec_decode_block_intra(a, block[block_index[i]],
yading@10:                                            block_index[i])) < 0)
yading@10:             return ret;
yading@10:         if (get_bits_left(&a->gb) < 0)
yading@10:             return AVERROR_INVALIDDATA;
yading@10:     }
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static inline void idct_put(MDECContext *a, AVFrame *frame, int mb_x, int mb_y)
yading@10: {
yading@10:     int16_t (*block)[64] = a->block;
yading@10:     int linesize = frame->linesize[0];
yading@10: 
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:     a->dsp.idct_put(dest_y,                    linesize, block[0]);
yading@10:     a->dsp.idct_put(dest_y                + 8, linesize, block[1]);
yading@10:     a->dsp.idct_put(dest_y + 8 * linesize,     linesize, block[2]);
yading@10:     a->dsp.idct_put(dest_y + 8 * linesize + 8, linesize, block[3]);
yading@10: 
yading@10:     if (!(a->avctx->flags & CODEC_FLAG_GRAY)) {
yading@10:         a->dsp.idct_put(dest_cb, frame->linesize[1], block[4]);
yading@10:         a->dsp.idct_put(dest_cr, frame->linesize[2], block[5]);
yading@10:     }
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:     MDECContext * const a = avctx->priv_data;
yading@10:     const uint8_t *buf    = avpkt->data;
yading@10:     int buf_size          = avpkt->size;
yading@10:     ThreadFrame frame     = { .f = data };
yading@10:     int i, ret;
yading@10: 
yading@10:     if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0)
yading@10:         return ret;
yading@10:     frame.f->pict_type = AV_PICTURE_TYPE_I;
yading@10:     frame.f->key_frame = 1;
yading@10: 
yading@10:     av_fast_malloc(&a->bitstream_buffer, &a->bitstream_buffer_size, buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
yading@10:     if (!a->bitstream_buffer)
yading@10:         return AVERROR(ENOMEM);
yading@10:     for (i = 0; i < buf_size; i += 2) {
yading@10:         a->bitstream_buffer[i]     = buf[i + 1];
yading@10:         a->bitstream_buffer[i + 1] = buf[i];
yading@10:     }
yading@10:     init_get_bits(&a->gb, a->bitstream_buffer, buf_size * 8);
yading@10: 
yading@10:     /* skip over 4 preamble bytes in stream (typically 0xXX 0xXX 0x00 0x38) */
yading@10:     skip_bits(&a->gb, 32);
yading@10: 
yading@10:     a->qscale  = get_bits(&a->gb, 16);
yading@10:     a->version = get_bits(&a->gb, 16);
yading@10: 
yading@10:     a->last_dc[0] = a->last_dc[1] = a->last_dc[2] = 128;
yading@10: 
yading@10:     for (a->mb_x = 0; a->mb_x < a->mb_width; a->mb_x++) {
yading@10:         for (a->mb_y = 0; a->mb_y < a->mb_height; a->mb_y++) {
yading@10:             if ((ret = decode_mb(a, a->block)) < 0)
yading@10:                 return ret;
yading@10: 
yading@10:             idct_put(a, frame.f, a->mb_x, a->mb_y);
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     *got_frame = 1;
yading@10: 
yading@10:     return (get_bits_count(&a->gb) + 31) / 32 * 4;
yading@10: }
yading@10: 
yading@10: static av_cold int decode_init(AVCodecContext *avctx)
yading@10: {
yading@10:     MDECContext * const a = avctx->priv_data;
yading@10: 
yading@10:     a->mb_width  = (avctx->coded_width  + 15) / 16;
yading@10:     a->mb_height = (avctx->coded_height + 15) / 16;
yading@10: 
yading@10:     a->avctx           = avctx;
yading@10: 
yading@10:     ff_dsputil_init(&a->dsp, avctx);
yading@10:     ff_mpeg12_init_vlcs();
yading@10:     ff_init_scantable(a->dsp.idct_permutation, &a->scantable, ff_zigzag_direct);
yading@10: 
yading@10:     if (avctx->idct_algo == FF_IDCT_AUTO)
yading@10:         avctx->idct_algo = FF_IDCT_SIMPLE;
yading@10:     avctx->pix_fmt  = AV_PIX_FMT_YUVJ420P;
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static av_cold int decode_init_thread_copy(AVCodecContext *avctx)
yading@10: {
yading@10:     MDECContext * const a = avctx->priv_data;
yading@10: 
yading@10:     a->avctx           = avctx;
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static av_cold int decode_end(AVCodecContext *avctx)
yading@10: {
yading@10:     MDECContext * const a = avctx->priv_data;
yading@10: 
yading@10:     av_freep(&a->bitstream_buffer);
yading@10:     a->bitstream_buffer_size = 0;
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: AVCodec ff_mdec_decoder = {
yading@10:     .name             = "mdec",
yading@10:     .type             = AVMEDIA_TYPE_VIDEO,
yading@10:     .id               = AV_CODEC_ID_MDEC,
yading@10:     .priv_data_size   = sizeof(MDECContext),
yading@10:     .init             = decode_init,
yading@10:     .close            = decode_end,
yading@10:     .decode           = decode_frame,
yading@10:     .capabilities     = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS,
yading@10:     .long_name        = NULL_IF_CONFIG_SMALL("Sony PlayStation MDEC (Motion DECoder)"),
yading@10:     .init_thread_copy = ONLY_IF_THREADS_ENABLED(decode_init_thread_copy)
yading@10: };