yading@10: /*
yading@10:  * Bitmap Brothers JV video decoder
yading@10:  * Copyright (c) 2011 Peter Ross <pross@xvid.org>
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:  * Bitmap Brothers JV video decoder
yading@10:  * @author Peter Ross <pross@xvid.org>
yading@10:  */
yading@10: 
yading@10: #include "avcodec.h"
yading@10: #include "dsputil.h"
yading@10: #include "get_bits.h"
yading@10: #include "internal.h"
yading@10: #include "libavutil/intreadwrite.h"
yading@10: 
yading@10: typedef struct JvContext {
yading@10:     DSPContext dsp;
yading@10:     AVFrame    frame;
yading@10:     uint32_t   palette[AVPALETTE_COUNT];
yading@10:     int        palette_has_changed;
yading@10: } JvContext;
yading@10: 
yading@10: static av_cold int decode_init(AVCodecContext *avctx)
yading@10: {
yading@10:     JvContext *s = avctx->priv_data;
yading@10:     avctx->pix_fmt = AV_PIX_FMT_PAL8;
yading@10:     ff_dsputil_init(&s->dsp, avctx);
yading@10:     avcodec_get_frame_defaults(&s->frame);
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Decode 2x2 block
yading@10:  */
yading@10: static inline void decode2x2(GetBitContext *gb, uint8_t *dst, int linesize)
yading@10: {
yading@10:     int i, j, v[2];
yading@10: 
yading@10:     switch (get_bits(gb, 2)) {
yading@10:     case 1:
yading@10:         v[0] = get_bits(gb, 8);
yading@10:         for (j = 0; j < 2; j++)
yading@10:             memset(dst + j*linesize, v[0], 2);
yading@10:         break;
yading@10:     case 2:
yading@10:         v[0] = get_bits(gb, 8);
yading@10:         v[1] = get_bits(gb, 8);
yading@10:         for (j = 0; j < 2; j++)
yading@10:             for (i = 0; i < 2; i++)
yading@10:                 dst[j*linesize + i] = v[get_bits1(gb)];
yading@10:         break;
yading@10:     case 3:
yading@10:         for (j = 0; j < 2; j++)
yading@10:             for (i = 0; i < 2; i++)
yading@10:                 dst[j*linesize + i] = get_bits(gb, 8);
yading@10:     }
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Decode 4x4 block
yading@10:  */
yading@10: static inline void decode4x4(GetBitContext *gb, uint8_t *dst, int linesize)
yading@10: {
yading@10:     int i, j, v[2];
yading@10: 
yading@10:     switch (get_bits(gb, 2)) {
yading@10:     case 1:
yading@10:         v[0] = get_bits(gb, 8);
yading@10:         for (j = 0; j < 4; j++)
yading@10:             memset(dst + j*linesize, v[0], 4);
yading@10:         break;
yading@10:     case 2:
yading@10:         v[0] = get_bits(gb, 8);
yading@10:         v[1] = get_bits(gb, 8);
yading@10:         for (j = 2; j >= 0; j -= 2) {
yading@10:             for (i = 0; i < 4; i++)
yading@10:                 dst[j*linesize + i]     = v[get_bits1(gb)];
yading@10:             for (i = 0; i < 4; i++)
yading@10:                 dst[(j+1)*linesize + i] = v[get_bits1(gb)];
yading@10:         }
yading@10:         break;
yading@10:     case 3:
yading@10:         for (j = 0; j < 4; j += 2)
yading@10:             for (i = 0; i < 4; i += 2)
yading@10:                 decode2x2(gb, dst + j*linesize + i, linesize);
yading@10:     }
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Decode 8x8 block
yading@10:  */
yading@10: static inline void decode8x8(GetBitContext *gb, uint8_t *dst, int linesize, DSPContext *dsp)
yading@10: {
yading@10:     int i, j, v[2];
yading@10: 
yading@10:     switch (get_bits(gb, 2)) {
yading@10:     case 1:
yading@10:         v[0] = get_bits(gb, 8);
yading@10:         dsp->fill_block_tab[1](dst, v[0], linesize, 8);
yading@10:         break;
yading@10:     case 2:
yading@10:         v[0] = get_bits(gb, 8);
yading@10:         v[1] = get_bits(gb, 8);
yading@10:         for (j = 7; j >= 0; j--)
yading@10:             for (i = 0; i <  8; i++)
yading@10:                 dst[j*linesize + i] = v[get_bits1(gb)];
yading@10:         break;
yading@10:     case 3:
yading@10:         for (j = 0; j < 8; j += 4)
yading@10:             for (i = 0; i < 8; i += 4)
yading@10:                 decode4x4(gb, dst + j*linesize + i, linesize);
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:     JvContext *s           = avctx->priv_data;
yading@10:     const uint8_t *buf     = avpkt->data;
yading@10:     const uint8_t *buf_end = buf + avpkt->size;
yading@10:     int video_size, video_type, i, j, ret;
yading@10: 
yading@10:     if (avpkt->size < 6)
yading@10:         return AVERROR_INVALIDDATA;
yading@10: 
yading@10:     video_size = AV_RL32(buf);
yading@10:     video_type = buf[4];
yading@10:     buf += 5;
yading@10: 
yading@10:     if (video_size) {
yading@10:         if (video_size < 0 || video_size > avpkt->size - 5) {
yading@10:             av_log(avctx, AV_LOG_ERROR, "video size %d invalid\n", video_size);
yading@10:             return AVERROR_INVALIDDATA;
yading@10:         }
yading@10:         if ((ret = ff_reget_buffer(avctx, &s->frame)) < 0)
yading@10:             return ret;
yading@10: 
yading@10:         if (video_type == 0 || video_type == 1) {
yading@10:             GetBitContext gb;
yading@10:             init_get_bits(&gb, buf, 8 * video_size);
yading@10: 
yading@10:             for (j = 0; j < avctx->height; j += 8)
yading@10:                 for (i = 0; i < avctx->width; i += 8)
yading@10:                     decode8x8(&gb, s->frame.data[0] + j*s->frame.linesize[0] + i,
yading@10:                               s->frame.linesize[0], &s->dsp);
yading@10: 
yading@10:             buf += video_size;
yading@10:         } else if (video_type == 2) {
yading@10:             int v = *buf++;
yading@10:             for (j = 0; j < avctx->height; j++)
yading@10:                 memset(s->frame.data[0] + j*s->frame.linesize[0], v, avctx->width);
yading@10:         } else {
yading@10:             av_log(avctx, AV_LOG_WARNING, "unsupported frame type %i\n", video_type);
yading@10:             return AVERROR_INVALIDDATA;
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     if (buf_end - buf >= AVPALETTE_COUNT * 3) {
yading@10:         for (i = 0; i < AVPALETTE_COUNT; i++) {
yading@10:             uint32_t pal = AV_RB24(buf);
yading@10:             s->palette[i] = 0xFFU << 24 | pal << 2 | ((pal >> 4) & 0x30303);
yading@10:             buf += 3;
yading@10:         }
yading@10:         s->palette_has_changed = 1;
yading@10:     }
yading@10: 
yading@10:     if (video_size) {
yading@10:         s->frame.key_frame           = 1;
yading@10:         s->frame.pict_type           = AV_PICTURE_TYPE_I;
yading@10:         s->frame.palette_has_changed = s->palette_has_changed;
yading@10:         s->palette_has_changed       = 0;
yading@10:         memcpy(s->frame.data[1], s->palette, AVPALETTE_SIZE);
yading@10: 
yading@10:         if ((ret = av_frame_ref(data, &s->frame)) < 0)
yading@10:             return ret;
yading@10:         *got_frame = 1;
yading@10:     }
yading@10: 
yading@10:     return avpkt->size;
yading@10: }
yading@10: 
yading@10: static av_cold int decode_close(AVCodecContext *avctx)
yading@10: {
yading@10:     JvContext *s = avctx->priv_data;
yading@10: 
yading@10:     av_frame_unref(&s->frame);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: AVCodec ff_jv_decoder = {
yading@10:     .name           = "jv",
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("Bitmap Brothers JV video"),
yading@10:     .type           = AVMEDIA_TYPE_VIDEO,
yading@10:     .id             = AV_CODEC_ID_JV,
yading@10:     .priv_data_size = sizeof(JvContext),
yading@10:     .init           = decode_init,
yading@10:     .close          = decode_close,
yading@10:     .decode         = decode_frame,
yading@10:     .capabilities   = CODEC_CAP_DR1,
yading@10: };