avcodec/sanm: SMUSH codec48 decoder

Adds a decoder for the SMUSH codec48 video encoding, as is used by
the LucasArts game "Mysteries of the Sith".

Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com>
Signed-off-by: Marton Balint <cus@passwd.hu>
This commit is contained in:
Manuel Lauss 2024-12-16 17:08:01 +01:00 committed by Marton Balint
parent dd5696c197
commit b22ce90d42

View file

@ -995,6 +995,227 @@ static int old_codec47(SANMVideoContext *ctx, int top,
return 0; return 0;
} }
// scale 4x4 input block to an 8x8 output block
static void c48_4to8(uint8_t *dst, const uint8_t *src, const uint16_t w)
{
uint16_t p;
// dst is always at least 16bit aligned
for (int i = 0; i < 4; i++) {
for (int j = 0; j < 8; j += 2) {
p = *src++;
p = (p << 8) | p;
*((uint16_t *)(dst + w * 0 + j)) = p;
*((uint16_t *)(dst + w * 1 + j)) = p;
}
dst += w * 2;
}
}
static int codec48_block(SANMVideoContext *ctx, uint8_t *dst, uint8_t *db,
const uint16_t w)
{
uint8_t opc, sb[16];
int i, j, k, l;
int16_t mvofs;
uint32_t ofs;
if (bytestream2_get_bytes_left(&ctx->gb) < 1)
return 1;
opc = bytestream2_get_byteu(&ctx->gb);
switch (opc) {
case 0xFF: // 1x1 -> 8x8 block scale
if (bytestream2_get_bytes_left(&ctx->gb) < 1)
return 1;
opc = bytestream2_get_byteu(&ctx->gb);
for (i = 0; i < 16; i++)
sb[i] = opc;
c48_4to8(dst, sb, w);
break;
case 0xFE: // 1x 8x8 copy from deltabuf, 16bit mv from source
if (bytestream2_get_bytes_left(&ctx->gb) < 2)
return 1;
mvofs = bytestream2_get_le16(&ctx->gb);
for (i = 0; i < 8; i++) {
ofs = w * i;
for (k = 0; k < 8; k++)
*(dst + ofs + k) = *(db + ofs + k + mvofs);
}
break;
case 0xFD: // 2x2 -> 8x8 block scale
if (bytestream2_get_bytes_left(&ctx->gb) < 4)
return 1;
sb[ 5] = bytestream2_get_byteu(&ctx->gb);
sb[ 7] = bytestream2_get_byteu(&ctx->gb);
sb[13] = bytestream2_get_byteu(&ctx->gb);
sb[15] = bytestream2_get_byteu(&ctx->gb);
sb[0] = sb[1] = sb[4] = sb[5];
sb[2] = sb[3] = sb[6] = sb[7];
sb[8] = sb[9] = sb[12] = sb[13];
sb[10] = sb[11] = sb[14] = sb[15];
c48_4to8(dst, sb, w);
break;
case 0xFC: // 4x copy 4x4 block, per-block c37_mv from source
if (bytestream2_get_bytes_left(&ctx->gb) < 4)
return 1;
for (i = 0; i < 8; i += 4) {
for (k = 0; k < 8; k += 4) {
opc = bytestream2_get_byteu(&ctx->gb);
mvofs = c37_mv[opc * 2] + (c37_mv[opc * 2 + 1] * w);
for (j = 0; j < 4; j++) {
ofs = (w * (j + i)) + k;
for (l = 0; l < 4; l++)
*(dst + ofs + l) = *(db + ofs + l + mvofs);
}
}
}
break;
case 0xFB: // Copy 4x 4x4 blocks, per-block mv from source
if (bytestream2_get_bytes_left(&ctx->gb) < 8)
return 1;
for (i = 0; i < 8; i += 4) {
for (k = 0; k < 8; k += 4) {
mvofs = bytestream2_get_le16(&ctx->gb);
for (j = 0; j < 4; j++) {
ofs = (w * (j + i)) + k;
for (l = 0; l < 4; l++)
*(dst + ofs + l) = *(db + ofs + l + mvofs);
}
}
}
break;
case 0xFA: // scale 4x4 input block to 8x8 dest block
if (bytestream2_get_bytes_left(&ctx->gb) < 16)
return 1;
bytestream2_get_bufferu(&ctx->gb, sb, 16);
c48_4to8(dst, sb, w);
break;
case 0xF9: // 16x 2x2 copy from delta, per-block c37_mv from source
if (bytestream2_get_bytes_left(&ctx->gb) < 16)
return 1;
for (i = 0; i < 8; i += 2) {
for (j = 0; j < 8; j += 2) {
ofs = (w * i) + j;
opc = bytestream2_get_byteu(&ctx->gb);
mvofs = c37_mv[opc * 2] + (c37_mv[opc * 2 + 1] * w);
for (l = 0; l < 2; l++) {
*(dst + ofs + l + 0) = *(db + ofs + l + 0 + mvofs);
*(dst + ofs + l + w) = *(db + ofs + l + w + mvofs);
}
}
}
break;
case 0xF8: // 16x 2x2 blocks copy, 16bit mv from source
if (bytestream2_get_bytes_left(&ctx->gb) < 32)
return 1;
for (i = 0; i < 8; i += 2) {
for (j = 0; j < 8; j += 2) {
ofs = w * i + j;
mvofs = bytestream2_get_le16(&ctx->gb);
for (l = 0; l < 2; l++) {
*(dst + ofs + l + 0) = *(db + ofs + l + 0 + mvofs);
*(dst + ofs + l + w) = *(db + ofs + l + w + mvofs);
}
}
}
break;
case 0xF7: // copy 8x8 block from src to dest
if (bytestream2_get_bytes_left(&ctx->gb) < 64)
return 1;
for (i = 0; i < 8; i++) {
ofs = i * w;
for (l = 0; l < 8; l++)
*(dst + ofs + l) = bytestream2_get_byteu(&ctx->gb);
}
break;
default: // copy 8x8 block from prev, c37_mv from source
mvofs = c37_mv[opc * 2] + (c37_mv[opc * 2 + 1] * w);
for (i = 0; i < 8; i++) {
ofs = i * w;
for (l = 0; l < 8; l++)
*(dst + ofs + l) = *(db + ofs + l + mvofs);
}
break;
}
return 0;
}
static int old_codec48(SANMVideoContext *ctx, int width, int height)
{
uint8_t *dst, *prev;
int compr = bytestream2_get_byte(&ctx->gb);
int mvidx = bytestream2_get_byte(&ctx->gb);
int seq = bytestream2_get_le16(&ctx->gb);
uint32_t decoded_size = bytestream2_get_le32(&ctx->gb);
int i, j, flags;
// all codec48 videos use 1, but just to be safe...
if (mvidx != 1) {
av_log(ctx->avctx, AV_LOG_ERROR, "Invalid motion base value %d.\n", mvidx);
return AVERROR_INVALIDDATA;
}
bytestream2_skip(&ctx->gb, 4);
flags = bytestream2_get_byte(&ctx->gb);
bytestream2_skip(&ctx->gb, 3);
if (flags & 8) {
if (bytestream2_get_bytes_left(&ctx->gb) < 0x8080)
return AVERROR_INVALIDDATA;
codec47_read_interptable(ctx);
}
dst = (uint8_t*)ctx->frm0;
prev = (uint8_t*)ctx->frm2;
if (!seq) {
ctx->prev_seq = -1;
memset(prev, 0, ctx->aligned_height * width);
}
switch (compr) {
case 0:
if (bytestream2_get_bytes_left(&ctx->gb) < width * height)
return AVERROR_INVALIDDATA;
for (j = 0; j < height; j++) {
bytestream2_get_bufferu(&ctx->gb, dst, width);
dst += width;
}
break;
case 2:
if (rle_decode(ctx, dst, decoded_size))
return AVERROR_INVALIDDATA;
break;
case 3:
if (seq == ctx->prev_seq + 1) {
for (j = 0; j < height; j += 8) {
for (i = 0; i < width; i += 8) {
if (codec48_block(ctx, dst + i, prev + i, width))
return AVERROR_INVALIDDATA;
}
dst += width * 8;
prev += width * 8;
}
}
break;
case 5:
if (bytestream2_get_bytes_left(&ctx->gb) < ((width + 1) >> 1) * ((height + 1) >> 1))
return AVERROR_INVALIDDATA;
codec47_comp1(ctx, dst, width, height, width);
break;
default:
avpriv_report_missing_feature(ctx->avctx,
"Subcodec 48 compression %d", compr);
return AVERROR_PATCHWELCOME;
}
ctx->rotate_code = 1; // swap frm[0] and frm[2]
ctx->prev_seq = seq;
return 0;
}
static int process_frame_obj(SANMVideoContext *ctx) static int process_frame_obj(SANMVideoContext *ctx)
{ {
uint16_t codec = bytestream2_get_le16u(&ctx->gb); uint16_t codec = bytestream2_get_le16u(&ctx->gb);
@ -1030,6 +1251,8 @@ static int process_frame_obj(SANMVideoContext *ctx)
return old_codec37(ctx, top, left, w, h); return old_codec37(ctx, top, left, w, h);
case 47: case 47:
return old_codec47(ctx, top, left, w, h); return old_codec47(ctx, top, left, w, h);
case 48:
return old_codec48(ctx, w, h);
default: default:
avpriv_request_sample(ctx->avctx, "Subcodec %d", codec); avpriv_request_sample(ctx->avctx, "Subcodec %d", codec);
return AVERROR_PATCHWELCOME; return AVERROR_PATCHWELCOME;