ffmpeg/libavcodec/rpza.c

285 lines
8.7 KiB
C

/*
* Quicktime Video (RPZA) Video Decoder
* Copyright (c) 2003 The FFmpeg Project
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* QT RPZA Video Decoder by Roberto Togni
* For more information about the RPZA format, visit:
* http://www.pcisys.net/~melanson/codecs/
*
* The RPZA decoder outputs RGB555 colorspace data.
*
* Note that this decoder reads big endian RGB555 pixel values from the
* bytestream, arranges them in the host's endian order, and outputs
* them to the final rendered map in the same host endian order. This is
* intended behavior as the libavcodec documentation states that RGB555
* pixels shall be stored in native CPU endianness.
*/
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "libavutil/internal.h"
#include "avcodec.h"
#include "bytestream.h"
#include "internal.h"
typedef struct RpzaContext {
AVCodecContext *avctx;
AVFrame *frame;
GetByteContext gb;
} RpzaContext;
#define ADVANCE_BLOCK() \
{ \
pixel_ptr += 4; \
if (pixel_ptr >= width) \
{ \
pixel_ptr = 0; \
row_ptr += stride * 4; \
} \
total_blocks--; \
if (total_blocks < 0) \
{ \
av_log(s->avctx, AV_LOG_ERROR, "warning: block counter just went negative (this should not happen)\n"); \
return; \
} \
}
static void rpza_decode_stream(RpzaContext *s)
{
int width = s->avctx->width;
int stride = s->frame->linesize[0] / 2;
int row_inc = stride - 4;
int chunk_size;
uint16_t colorA = 0, colorB;
uint16_t color4[4];
uint16_t ta, tb;
uint16_t *pixels = (uint16_t *)s->frame->data[0];
int row_ptr = 0;
int pixel_ptr = -4;
int block_ptr;
int pixel_x, pixel_y;
int total_blocks;
/* First byte is always 0xe1. Warn if it's different */
if (bytestream2_peek_byte(&s->gb) != 0xe1)
av_log(s->avctx, AV_LOG_ERROR, "First chunk byte is 0x%02x instead of 0xe1\n",
bytestream2_peek_byte(&s->gb));
/* Get chunk size, ingnoring first byte */
chunk_size = bytestream2_get_be32(&s->gb) & 0x00FFFFFF;
/* If length mismatch use size from MOV file and try to decode anyway */
if (chunk_size != bytestream2_get_bytes_left(&s->gb) + 4)
av_log(s->avctx, AV_LOG_WARNING,
"MOV chunk size %d != encoded chunk size %d\n",
chunk_size,
bytestream2_get_bytes_left(&s->gb) + 4
);
/* Number of 4x4 blocks in frame. */
total_blocks = ((s->avctx->width + 3) / 4) * ((s->avctx->height + 3) / 4);
/* Process chunk data */
while (bytestream2_get_bytes_left(&s->gb)) {
uint8_t opcode = bytestream2_get_byte(&s->gb); /* Get opcode */
int n_blocks = (opcode & 0x1f) + 1; /* Extract block counter from opcode */
/* If opcode MSbit is 0, we need more data to decide what to do */
if ((opcode & 0x80) == 0) {
colorA = (opcode << 8) | bytestream2_get_byte(&s->gb);
opcode = 0;
if ((bytestream2_peek_byte(&s->gb) & 0x80) != 0) {
/* Must behave as opcode 110xxxxx, using colorA computed
* above. Use fake opcode 0x20 to enter switch block at
* the right place */
opcode = 0x20;
n_blocks = 1;
}
}
n_blocks = FFMIN(n_blocks, total_blocks);
switch (opcode & 0xe0) {
/* Skip blocks */
case 0x80:
while (n_blocks--) {
ADVANCE_BLOCK();
}
break;
/* Fill blocks with one color */
case 0xa0:
colorA = bytestream2_get_be16(&s->gb);
while (n_blocks--) {
ADVANCE_BLOCK()
block_ptr = row_ptr + pixel_ptr;
for (pixel_y = 0; pixel_y < 4; pixel_y++) {
for (pixel_x = 0; pixel_x < 4; pixel_x++){
pixels[block_ptr] = colorA;
block_ptr++;
}
block_ptr += row_inc;
}
}
break;
/* Fill blocks with 4 colors */
case 0xc0:
colorA = bytestream2_get_be16(&s->gb);
case 0x20:
colorB = bytestream2_get_be16(&s->gb);
/* sort out the colors */
color4[0] = colorB;
color4[1] = 0;
color4[2] = 0;
color4[3] = colorA;
/* red components */
ta = (colorA >> 10) & 0x1F;
tb = (colorB >> 10) & 0x1F;
color4[1] |= ((11 * ta + 21 * tb) >> 5) << 10;
color4[2] |= ((21 * ta + 11 * tb) >> 5) << 10;
/* green components */
ta = (colorA >> 5) & 0x1F;
tb = (colorB >> 5) & 0x1F;
color4[1] |= ((11 * ta + 21 * tb) >> 5) << 5;
color4[2] |= ((21 * ta + 11 * tb) >> 5) << 5;
/* blue components */
ta = colorA & 0x1F;
tb = colorB & 0x1F;
color4[1] |= ((11 * ta + 21 * tb) >> 5);
color4[2] |= ((21 * ta + 11 * tb) >> 5);
if (bytestream2_get_bytes_left(&s->gb) < n_blocks * 4)
return;
while (n_blocks--) {
ADVANCE_BLOCK();
block_ptr = row_ptr + pixel_ptr;
for (pixel_y = 0; pixel_y < 4; pixel_y++) {
uint8_t index = bytestream2_get_byteu(&s->gb);
for (pixel_x = 0; pixel_x < 4; pixel_x++){
uint8_t idx = (index >> (2 * (3 - pixel_x))) & 0x03;
pixels[block_ptr] = color4[idx];
block_ptr++;
}
block_ptr += row_inc;
}
}
break;
/* Fill block with 16 colors */
case 0x00:
if (bytestream2_get_bytes_left(&s->gb) < 30)
return;
ADVANCE_BLOCK();
block_ptr = row_ptr + pixel_ptr;
for (pixel_y = 0; pixel_y < 4; pixel_y++) {
for (pixel_x = 0; pixel_x < 4; pixel_x++){
/* We already have color of upper left pixel */
if ((pixel_y != 0) || (pixel_x != 0))
colorA = bytestream2_get_be16u(&s->gb);
pixels[block_ptr] = colorA;
block_ptr++;
}
block_ptr += row_inc;
}
break;
/* Unknown opcode */
default:
av_log(s->avctx, AV_LOG_ERROR, "Unknown opcode %d in rpza chunk."
" Skip remaining %d bytes of chunk data.\n", opcode,
bytestream2_get_bytes_left(&s->gb));
return;
} /* Opcode switch */
}
}
static av_cold int rpza_decode_init(AVCodecContext *avctx)
{
RpzaContext *s = avctx->priv_data;
s->avctx = avctx;
avctx->pix_fmt = AV_PIX_FMT_RGB555;
s->frame = av_frame_alloc();
if (!s->frame)
return AVERROR(ENOMEM);
return 0;
}
static int rpza_decode_frame(AVCodecContext *avctx,
void *data, int *got_frame,
AVPacket *avpkt)
{
RpzaContext *s = avctx->priv_data;
int ret;
bytestream2_init(&s->gb, avpkt->data, avpkt->size);
if ((ret = ff_reget_buffer(avctx, s->frame)) < 0)
return ret;
rpza_decode_stream(s);
if ((ret = av_frame_ref(data, s->frame)) < 0)
return ret;
*got_frame = 1;
/* always report that the buffer was completely consumed */
return avpkt->size;
}
static av_cold int rpza_decode_end(AVCodecContext *avctx)
{
RpzaContext *s = avctx->priv_data;
av_frame_free(&s->frame);
return 0;
}
AVCodec ff_rpza_decoder = {
.name = "rpza",
.long_name = NULL_IF_CONFIG_SMALL("QuickTime video (RPZA)"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_RPZA,
.priv_data_size = sizeof(RpzaContext),
.init = rpza_decode_init,
.close = rpza_decode_end,
.decode = rpza_decode_frame,
.capabilities = AV_CODEC_CAP_DR1,
};