X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fqpeg.c;h=caf28e3fbc2f896c11e7508df48eabd7526af86d;hb=67235dfa1d2b4bab2c8015e5b8e43ea63a681892;hp=bbb9f71aae5c6adc4b25b142dbf858dbbb5bcb7e;hpb=e986a5d10d95b62cd85aaefc7d4da34699fbedeb;p=ffmpeg diff --git a/libavcodec/qpeg.c b/libavcodec/qpeg.c index bbb9f71aae5..caf28e3fbc2 100644 --- a/libavcodec/qpeg.c +++ b/libavcodec/qpeg.c @@ -25,15 +25,17 @@ */ #include "avcodec.h" +#include "bytestream.h" typedef struct QpegContext{ AVCodecContext *avctx; AVFrame pic, ref; uint32_t pal[256]; + GetByteContext buffer; } QpegContext; -static int qpeg_decode_intra(const uint8_t *src, uint8_t *dst, int size, - int stride, int width, int height) +static void qpeg_decode_intra(QpegContext *qctx, uint8_t *dst, + int stride, int width, int height) { int i; int code; @@ -46,31 +48,26 @@ static int qpeg_decode_intra(const uint8_t *src, uint8_t *dst, int size, height--; dst = dst + height * stride; - while((size > 0) && (rows_to_go > 0)) { - code = *src++; - size--; + while ((bytestream2_get_bytes_left(&qctx->buffer) > 0) && (rows_to_go > 0)) { + code = bytestream2_get_byte(&qctx->buffer); run = copy = 0; if(code == 0xFC) /* end-of-picture code */ break; if(code >= 0xF8) { /* very long run */ - c0 = *src++; - c1 = *src++; - size -= 2; + c0 = bytestream2_get_byte(&qctx->buffer); + c1 = bytestream2_get_byte(&qctx->buffer); run = ((code & 0x7) << 16) + (c0 << 8) + c1 + 2; } else if (code >= 0xF0) { /* long run */ - c0 = *src++; - size--; + c0 = bytestream2_get_byte(&qctx->buffer); run = ((code & 0xF) << 8) + c0 + 2; } else if (code >= 0xE0) { /* short run */ run = (code & 0x1F) + 2; } else if (code >= 0xC0) { /* very long copy */ - c0 = *src++; - c1 = *src++; - size -= 2; + c0 = bytestream2_get_byte(&qctx->buffer); + c1 = bytestream2_get_byte(&qctx->buffer); copy = ((code & 0x3F) << 16) + (c0 << 8) + c1 + 1; } else if (code >= 0x80) { /* long copy */ - c0 = *src++; - size--; + c0 = bytestream2_get_byte(&qctx->buffer); copy = ((code & 0x7F) << 8) + c0 + 1; } else { /* short copy */ copy = code + 1; @@ -80,8 +77,7 @@ static int qpeg_decode_intra(const uint8_t *src, uint8_t *dst, int size, if(run) { int p; - p = *src++; - size--; + p = bytestream2_get_byte(&qctx->buffer); for(i = 0; i < run; i++) { dst[filled++] = p; if (filled >= width) { @@ -93,11 +89,8 @@ static int qpeg_decode_intra(const uint8_t *src, uint8_t *dst, int size, } } } else { - size -= copy; - if (size<0) - return AVERROR_INVALIDDATA; for(i = 0; i < copy; i++) { - dst[filled++] = *src++; + dst[filled++] = bytestream2_get_byte(&qctx->buffer); if (filled >= width) { filled = 0; dst -= stride; @@ -108,7 +101,6 @@ static int qpeg_decode_intra(const uint8_t *src, uint8_t *dst, int size, } } } - return 0; } static const int qpeg_table_h[16] = @@ -117,9 +109,10 @@ static const int qpeg_table_w[16] = { 0x00, 0x20, 0x18, 0x08, 0x18, 0x10, 0x20, 0x10, 0x08, 0x10, 0x20, 0x20, 0x08, 0x10, 0x18, 0x04}; /* Decodes delta frames */ -static void qpeg_decode_inter(const uint8_t *src, uint8_t *dst, int size, - int stride, int width, int height, - int delta, const uint8_t *ctable, uint8_t *refdata) +static void qpeg_decode_inter(QpegContext *qctx, uint8_t *dst, + int stride, int width, int height, + int delta, const uint8_t *ctable, + uint8_t *refdata) { int i, j; int code; @@ -137,13 +130,12 @@ static void qpeg_decode_inter(const uint8_t *src, uint8_t *dst, int size, height--; dst = dst + height * stride; - while((size > 0) && (height >= 0)) { - code = *src++; - size--; + while ((bytestream2_get_bytes_left(&qctx->buffer) > 0) && (height >= 0)) { + code = bytestream2_get_byte(&qctx->buffer); if(delta) { /* motion compensation */ - while((code & 0xF0) == 0xF0) { + while(bytestream2_get_bytes_left(&qctx->buffer) > 0 && (code & 0xF0) == 0xF0) { if(delta == 1) { int me_idx; int me_w, me_h, me_x, me_y; @@ -156,8 +148,7 @@ static void qpeg_decode_inter(const uint8_t *src, uint8_t *dst, int size, me_h = qpeg_table_h[me_idx]; /* extract motion vector */ - corr = *src++; - size--; + corr = bytestream2_get_byte(&qctx->buffer); val = corr >> 4; if(val > 7) @@ -184,8 +175,7 @@ static void qpeg_decode_inter(const uint8_t *src, uint8_t *dst, int size, } } } - code = *src++; - size--; + code = bytestream2_get_byte(&qctx->buffer); } } @@ -195,28 +185,33 @@ static void qpeg_decode_inter(const uint8_t *src, uint8_t *dst, int size, int p; code &= 0x1F; - p = *src++; - size--; + p = bytestream2_get_byte(&qctx->buffer); for(i = 0; i <= code; i++) { dst[filled++] = p; if(filled >= width) { filled = 0; dst -= stride; height--; + if(height < 0) + break; } } } else if(code >= 0xC0) { /* copy code: 0xC0..0xDF */ code &= 0x1F; + if(code + 1 > bytestream2_get_bytes_left(&qctx->buffer)) + break; + for(i = 0; i <= code; i++) { - dst[filled++] = *src++; + dst[filled++] = bytestream2_get_byte(&qctx->buffer); if(filled >= width) { filled = 0; dst -= stride; height--; + if(height < 0) + break; } } - size -= code + 1; } else if(code >= 0x80) { /* skip code: 0x80..0xBF */ int skip; @@ -224,9 +219,9 @@ static void qpeg_decode_inter(const uint8_t *src, uint8_t *dst, int size, /* codes 0x80 and 0x81 are actually escape codes, skip value minus constant is in the next byte */ if(!code) - skip = (*src++) + 64; + skip = bytestream2_get_byte(&qctx->buffer) + 64; else if(code == 1) - skip = (*src++) + 320; + skip = bytestream2_get_byte(&qctx->buffer) + 320; else skip = code; filled += skip; @@ -239,8 +234,9 @@ static void qpeg_decode_inter(const uint8_t *src, uint8_t *dst, int size, } } else { /* zero code treated as one-pixel skip */ - if(code) + if(code) { dst[filled++] = ctable[code & 0x7F]; + } else filled++; if(filled >= width) { @@ -256,15 +252,21 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt) { - const uint8_t *buf = avpkt->data; - int buf_size = avpkt->size; + uint8_t ctable[128]; QpegContext * const a = avctx->priv_data; - AVFrame * p= (AVFrame*)&a->pic; - AVFrame * ref= (AVFrame*)&a->ref; + AVFrame * p = &a->pic; + AVFrame * ref= &a->ref; uint8_t* outdata; - int delta, ret = 0; + int delta; const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL); + if (avpkt->size < 0x86) { + av_log(avctx, AV_LOG_ERROR, "Packet is too small\n"); + return AVERROR_INVALIDDATA; + } + + bytestream2_init(&a->buffer, avpkt->data, avpkt->size); + if(ref->data[0]) avctx->release_buffer(avctx, ref); FFSWAP(AVFrame, *ref, *p); @@ -275,16 +277,17 @@ static int decode_frame(AVCodecContext *avctx, return -1; } outdata = a->pic.data[0]; - if(buf[0x85] == 0x10) { - ret = qpeg_decode_intra(buf+0x86, outdata, buf_size - 0x86, a->pic.linesize[0], avctx->width, avctx->height); + bytestream2_skip(&a->buffer, 4); + bytestream2_get_buffer(&a->buffer, ctable, 128); + bytestream2_skip(&a->buffer, 1); + + delta = bytestream2_get_byte(&a->buffer); + if(delta == 0x10) { + qpeg_decode_intra(a, outdata, a->pic.linesize[0], avctx->width, avctx->height); } else { - delta = buf[0x85]; - qpeg_decode_inter(buf+0x86, outdata, buf_size - 0x86, a->pic.linesize[0], avctx->width, avctx->height, delta, buf + 4, a->ref.data[0]); + qpeg_decode_inter(a, outdata, a->pic.linesize[0], avctx->width, avctx->height, delta, ctable, a->ref.data[0]); } - if (ret<0) - return ret; - /* make the palette available on the way out */ if (pal) { a->pic.palette_has_changed = 1; @@ -295,7 +298,7 @@ static int decode_frame(AVCodecContext *avctx, *data_size = sizeof(AVFrame); *(AVFrame*)data = a->pic; - return buf_size; + return avpkt->size; } static av_cold int decode_init(AVCodecContext *avctx){ @@ -311,8 +314,8 @@ static av_cold int decode_init(AVCodecContext *avctx){ static av_cold int decode_end(AVCodecContext *avctx){ QpegContext * const a = avctx->priv_data; - AVFrame * const p= (AVFrame*)&a->pic; - AVFrame * const ref= (AVFrame*)&a->ref; + AVFrame * const p = &a->pic; + AVFrame * const ref= &a->ref; if(p->data[0]) avctx->release_buffer(avctx, p);