yading@10: /*
yading@10:  * Quicktime Video (RPZA) Video Decoder
yading@10:  * Copyright (C) 2003 the ffmpeg project
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:  * QT RPZA Video Decoder by Roberto Togni
yading@10:  * For more information about the RPZA format, visit:
yading@10:  *   http://www.pcisys.net/~melanson/codecs/
yading@10:  *
yading@10:  * The RPZA decoder outputs RGB555 colorspace data.
yading@10:  *
yading@10:  * Note that this decoder reads big endian RGB555 pixel values from the
yading@10:  * bytestream, arranges them in the host's endian order, and outputs
yading@10:  * them to the final rendered map in the same host endian order. This is
yading@10:  * intended behavior as the libavcodec documentation states that RGB555
yading@10:  * pixels shall be stored in native CPU endianness.
yading@10:  */
yading@10: 
yading@10: #include <stdio.h>
yading@10: #include <stdlib.h>
yading@10: #include <string.h>
yading@10: 
yading@10: #include "libavutil/internal.h"
yading@10: #include "libavutil/intreadwrite.h"
yading@10: #include "avcodec.h"
yading@10: #include "internal.h"
yading@10: 
yading@10: typedef struct RpzaContext {
yading@10: 
yading@10:     AVCodecContext *avctx;
yading@10:     AVFrame frame;
yading@10: 
yading@10:     const unsigned char *buf;
yading@10:     int size;
yading@10: 
yading@10: } RpzaContext;
yading@10: 
yading@10: #define ADVANCE_BLOCK() \
yading@10: { \
yading@10:     pixel_ptr += 4; \
yading@10:     if (pixel_ptr >= width) \
yading@10:     { \
yading@10:         pixel_ptr = 0; \
yading@10:         row_ptr += stride * 4; \
yading@10:     } \
yading@10:     total_blocks--; \
yading@10:     if (total_blocks < 0) \
yading@10:     { \
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "warning: block counter just went negative (this should not happen)\n"); \
yading@10:         return; \
yading@10:     } \
yading@10: }
yading@10: 
yading@10: static void rpza_decode_stream(RpzaContext *s)
yading@10: {
yading@10:     int width = s->avctx->width;
yading@10:     int stride = s->frame.linesize[0] / 2;
yading@10:     int row_inc = stride - 4;
yading@10:     int stream_ptr = 0;
yading@10:     int chunk_size;
yading@10:     unsigned char opcode;
yading@10:     int n_blocks;
yading@10:     unsigned short colorA = 0, colorB;
yading@10:     unsigned short color4[4];
yading@10:     unsigned char index, idx;
yading@10:     unsigned short ta, tb;
yading@10:     unsigned short *pixels = (unsigned short *)s->frame.data[0];
yading@10: 
yading@10:     int row_ptr = 0;
yading@10:     int pixel_ptr = 0;
yading@10:     int block_ptr;
yading@10:     int pixel_x, pixel_y;
yading@10:     int total_blocks;
yading@10: 
yading@10:     /* First byte is always 0xe1. Warn if it's different */
yading@10:     if (s->buf[stream_ptr] != 0xe1)
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "First chunk byte is 0x%02x instead of 0xe1\n",
yading@10:             s->buf[stream_ptr]);
yading@10: 
yading@10:     /* Get chunk size, ingnoring first byte */
yading@10:     chunk_size = AV_RB32(&s->buf[stream_ptr]) & 0x00FFFFFF;
yading@10:     stream_ptr += 4;
yading@10: 
yading@10:     /* If length mismatch use size from MOV file and try to decode anyway */
yading@10:     if (chunk_size != s->size)
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "MOV chunk size != encoded chunk size; using MOV chunk size\n");
yading@10: 
yading@10:     chunk_size = s->size;
yading@10: 
yading@10:     /* Number of 4x4 blocks in frame. */
yading@10:     total_blocks = ((s->avctx->width + 3) / 4) * ((s->avctx->height + 3) / 4);
yading@10: 
yading@10:     /* Process chunk data */
yading@10:     while (stream_ptr < chunk_size) {
yading@10:         opcode = s->buf[stream_ptr++]; /* Get opcode */
yading@10: 
yading@10:         n_blocks = (opcode & 0x1f) + 1; /* Extract block counter from opcode */
yading@10: 
yading@10:         /* If opcode MSbit is 0, we need more data to decide what to do */
yading@10:         if ((opcode & 0x80) == 0) {
yading@10:             colorA = (opcode << 8) | (s->buf[stream_ptr++]);
yading@10:             opcode = 0;
yading@10:             if ((s->buf[stream_ptr] & 0x80) != 0) {
yading@10:                 /* Must behave as opcode 110xxxxx, using colorA computed
yading@10:                  * above. Use fake opcode 0x20 to enter switch block at
yading@10:                  * the right place */
yading@10:                 opcode = 0x20;
yading@10:                 n_blocks = 1;
yading@10:             }
yading@10:         }
yading@10: 
yading@10:         switch (opcode & 0xe0) {
yading@10: 
yading@10:         /* Skip blocks */
yading@10:         case 0x80:
yading@10:             while (n_blocks--) {
yading@10:               ADVANCE_BLOCK();
yading@10:             }
yading@10:             break;
yading@10: 
yading@10:         /* Fill blocks with one color */
yading@10:         case 0xa0:
yading@10:             colorA = AV_RB16 (&s->buf[stream_ptr]);
yading@10:             stream_ptr += 2;
yading@10:             while (n_blocks--) {
yading@10:                 block_ptr = row_ptr + pixel_ptr;
yading@10:                 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
yading@10:                     for (pixel_x = 0; pixel_x < 4; pixel_x++){
yading@10:                         pixels[block_ptr] = colorA;
yading@10:                         block_ptr++;
yading@10:                     }
yading@10:                     block_ptr += row_inc;
yading@10:                 }
yading@10:                 ADVANCE_BLOCK();
yading@10:             }
yading@10:             break;
yading@10: 
yading@10:         /* Fill blocks with 4 colors */
yading@10:         case 0xc0:
yading@10:             colorA = AV_RB16 (&s->buf[stream_ptr]);
yading@10:             stream_ptr += 2;
yading@10:         case 0x20:
yading@10:             colorB = AV_RB16 (&s->buf[stream_ptr]);
yading@10:             stream_ptr += 2;
yading@10: 
yading@10:             /* sort out the colors */
yading@10:             color4[0] = colorB;
yading@10:             color4[1] = 0;
yading@10:             color4[2] = 0;
yading@10:             color4[3] = colorA;
yading@10: 
yading@10:             /* red components */
yading@10:             ta = (colorA >> 10) & 0x1F;
yading@10:             tb = (colorB >> 10) & 0x1F;
yading@10:             color4[1] |= ((11 * ta + 21 * tb) >> 5) << 10;
yading@10:             color4[2] |= ((21 * ta + 11 * tb) >> 5) << 10;
yading@10: 
yading@10:             /* green components */
yading@10:             ta = (colorA >> 5) & 0x1F;
yading@10:             tb = (colorB >> 5) & 0x1F;
yading@10:             color4[1] |= ((11 * ta + 21 * tb) >> 5) << 5;
yading@10:             color4[2] |= ((21 * ta + 11 * tb) >> 5) << 5;
yading@10: 
yading@10:             /* blue components */
yading@10:             ta = colorA & 0x1F;
yading@10:             tb = colorB & 0x1F;
yading@10:             color4[1] |= ((11 * ta + 21 * tb) >> 5);
yading@10:             color4[2] |= ((21 * ta + 11 * tb) >> 5);
yading@10: 
yading@10:             if (s->size - stream_ptr < n_blocks * 4)
yading@10:                 return;
yading@10:             while (n_blocks--) {
yading@10:                 block_ptr = row_ptr + pixel_ptr;
yading@10:                 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
yading@10:                     index = s->buf[stream_ptr++];
yading@10:                     for (pixel_x = 0; pixel_x < 4; pixel_x++){
yading@10:                         idx = (index >> (2 * (3 - pixel_x))) & 0x03;
yading@10:                         pixels[block_ptr] = color4[idx];
yading@10:                         block_ptr++;
yading@10:                     }
yading@10:                     block_ptr += row_inc;
yading@10:                 }
yading@10:                 ADVANCE_BLOCK();
yading@10:             }
yading@10:             break;
yading@10: 
yading@10:         /* Fill block with 16 colors */
yading@10:         case 0x00:
yading@10:             if (s->size - stream_ptr < 16)
yading@10:                 return;
yading@10:             block_ptr = row_ptr + pixel_ptr;
yading@10:             for (pixel_y = 0; pixel_y < 4; pixel_y++) {
yading@10:                 for (pixel_x = 0; pixel_x < 4; pixel_x++){
yading@10:                     /* We already have color of upper left pixel */
yading@10:                     if ((pixel_y != 0) || (pixel_x !=0)) {
yading@10:                         colorA = AV_RB16 (&s->buf[stream_ptr]);
yading@10:                         stream_ptr += 2;
yading@10:                     }
yading@10:                     pixels[block_ptr] = colorA;
yading@10:                     block_ptr++;
yading@10:                 }
yading@10:                 block_ptr += row_inc;
yading@10:             }
yading@10:             ADVANCE_BLOCK();
yading@10:             break;
yading@10: 
yading@10:         /* Unknown opcode */
yading@10:         default:
yading@10:             av_log(s->avctx, AV_LOG_ERROR, "Unknown opcode %d in rpza chunk."
yading@10:                  " Skip remaining %d bytes of chunk data.\n", opcode,
yading@10:                  chunk_size - stream_ptr);
yading@10:             return;
yading@10:         } /* Opcode switch */
yading@10:     }
yading@10: }
yading@10: 
yading@10: static av_cold int rpza_decode_init(AVCodecContext *avctx)
yading@10: {
yading@10:     RpzaContext *s = avctx->priv_data;
yading@10: 
yading@10:     s->avctx = avctx;
yading@10:     avctx->pix_fmt = AV_PIX_FMT_RGB555;
yading@10: 
yading@10:     avcodec_get_frame_defaults(&s->frame);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int rpza_decode_frame(AVCodecContext *avctx,
yading@10:                              void *data, int *got_frame,
yading@10:                              AVPacket *avpkt)
yading@10: {
yading@10:     const uint8_t *buf = avpkt->data;
yading@10:     int buf_size = avpkt->size;
yading@10:     RpzaContext *s = avctx->priv_data;
yading@10:     int ret;
yading@10: 
yading@10:     s->buf = buf;
yading@10:     s->size = buf_size;
yading@10: 
yading@10:     if ((ret = ff_reget_buffer(avctx, &s->frame)) < 0)
yading@10:         return ret;
yading@10: 
yading@10:     rpza_decode_stream(s);
yading@10: 
yading@10:     if ((ret = av_frame_ref(data, &s->frame)) < 0)
yading@10:         return ret;
yading@10: 
yading@10:     *got_frame      = 1;
yading@10: 
yading@10:     /* always report that the buffer was completely consumed */
yading@10:     return buf_size;
yading@10: }
yading@10: 
yading@10: static av_cold int rpza_decode_end(AVCodecContext *avctx)
yading@10: {
yading@10:     RpzaContext *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_rpza_decoder = {
yading@10:     .name           = "rpza",
yading@10:     .type           = AVMEDIA_TYPE_VIDEO,
yading@10:     .id             = AV_CODEC_ID_RPZA,
yading@10:     .priv_data_size = sizeof(RpzaContext),
yading@10:     .init           = rpza_decode_init,
yading@10:     .close          = rpza_decode_end,
yading@10:     .decode         = rpza_decode_frame,
yading@10:     .capabilities   = CODEC_CAP_DR1,
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("QuickTime video (RPZA)"),
yading@10: };