[FFmpeg-devel] [PATCH 1/6] Frame-based multithreading framework using pthreads
Alexander Strange
astrange
Mon Nov 15 14:37:01 CET 2010
See doc/multithreading.txt for details on use in codecs.
---
doc/APIchanges | 5 +
doc/multithreading.txt | 63 +++++
libavcodec/avcodec.h | 80 ++++++-
libavcodec/options.c | 4 +
libavcodec/pthread.c | 656 +++++++++++++++++++++++++++++++++++++++++++++++-
libavcodec/thread.h | 98 +++++++
libavcodec/utils.c | 64 +++++-
libavcodec/w32thread.c | 6 +
libavformat/utils.c | 5 +
libavutil/internal.h | 11 +
10 files changed, 979 insertions(+), 13 deletions(-)
create mode 100644 doc/multithreading.txt
create mode 100644 libavcodec/thread.h
diff --git a/doc/APIchanges b/doc/APIchanges
index b6806f8..c8892d9 100644
--- a/doc/APIchanges
+++ b/doc/APIchanges
@@ -13,6 +13,11 @@ libavutil: 2009-03-08
API changes, most recent first:
+2010-11-XX - rX - lavc 52.xx.0 - threading API
+ Add CODEC_CAP_FRAME_THREADS with new restrictions on get_buffer()/
+ release_buffer()/draw_horiz_band() callbacks for appropriate codecs.
+ Add thread_type and active_thread_type fields to AVCodecContext.
+
2010-11-13 - r25745 - lavc 52.95.0 - AVCodecContext
Add AVCodecContext.subtitle_header and AVCodecContext.subtitle_header_size
fields.
diff --git a/doc/multithreading.txt b/doc/multithreading.txt
new file mode 100644
index 0000000..65bdfb1
--- /dev/null
+++ b/doc/multithreading.txt
@@ -0,0 +1,63 @@
+FFmpeg multithreading methods
+==============================================
+
+FFmpeg provides two methods for multithreading codecs.
+
+Slice threading decodes multiple parts of a frame at the same time, using
+AVCodecContext execute() and execute2().
+
+Frame threading decodes multiple frames at the same time.
+It accepts N future frames and delays decoded pictures by N-1 frames.
+The later frames are decoded in separate threads while the user is
+displaying the current one.
+
+Restrictions on clients
+==============================================
+
+Slice threading -
+* The client's draw_horiz_band() must be thread-safe according to the comment
+ in avcodec.h.
+
+Frame threading -
+* Restrictions with slice threading also apply.
+* The client's get_buffer() and release_buffer() must be thread-safe as well.
+* There is one frame of delay added for every thread beyond the first one.
+ Clients using dts must account for the delay; pts sent through reordered_opaque
+ will work as usual.
+
+Restrictions on codec implementations
+==============================================
+
+Slice threading -
+ None except that there must be something worth executing in parallel.
+
+Frame threading -
+* Codecs can only accept entire pictures per packet.
+* Codecs similar to ffv1, whose streams don't reset across frames,
+ will not work because their bitstreams cannot be decoded in parallel.
+
+* The contents of buffers must not be read before ff_thread_await_progress()
+ has been called on them. reget_buffer() and buffer age optimizations no longer work.
+* The contents of buffers must not be written to after ff_thread_report_progress()
+ has been called on them. This includes draw_edges().
+
+Porting codecs to frame threading
+==============================================
+
+Find all context variables that are needed by the next frame. Move all
+code changing them up to before the decode process starts. Call ff_thread_finish_setup()
+afterwards. If some code can't be moved, have update_thread_context() run it
+in the next thread.
+
+If the codec allocates writable tables in its init(), add an init_thread_copy()
+which re-allocates them for other threads.
+
+Add CODEC_CAP_FRAME_THREADS to the codec capabilities. There will be very little
+speed gain at this point but it should work.
+
+Call ff_thread_report_progress() after some part of the current picture has decoded.
+A good place to put this is where draw_horiz_band() is called - add this if it isn't
+called anywhere, as it's useful too and the implementation is trivial when you're
+doing this. Note that draw_edges() needs to be called before reporting progress.
+
+Before accessing a reference frame or its MVs, call ff_thread_await_progress().
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index bff9477..e35e77d 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -32,7 +32,7 @@
#include "libavutil/cpu.h"
#define LIBAVCODEC_VERSION_MAJOR 52
-#define LIBAVCODEC_VERSION_MINOR 96
+#define LIBAVCODEC_VERSION_MINOR 97
#define LIBAVCODEC_VERSION_MICRO 0
#define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
@@ -711,7 +711,10 @@ typedef struct RcOverride{
* Codec should fill in channel configuration and samplerate instead of container
*/
#define CODEC_CAP_CHANNEL_CONF 0x0400
-
+/**
+* Codec supports frame-level multithreading.
+*/
+#define CODEC_CAP_FRAME_THREADS 0x0800
//The following defines may change, don't expect compatibility if you use them.
#define MB_TYPE_INTRA4x4 0x0001
@@ -992,7 +995,20 @@ typedef struct AVPanScan{
* - decoding: Set by libavcodec\
*/\
void *hwaccel_picture_private;\
-
+\
+ /**\
+ * the AVCodecContext which ff_thread_get_buffer() was last called on\
+ * - encoding: Set by libavcodec.\
+ * - decoding: Set by libavcodec.\
+ */\
+ struct AVCodecContext *owner;\
+\
+ /**\
+ * used by multithreading to store frame-specific info\
+ * - encoding: Set by libavcodec.\
+ * - decoding: Set by libavcodec.\
+ */\
+ void *thread_opaque;
#define FF_QSCALE_TYPE_MPEG1 0
#define FF_QSCALE_TYPE_MPEG2 1
@@ -1203,7 +1219,8 @@ typedef struct AVCodecContext {
* If non NULL, 'draw_horiz_band' is called by the libavcodec
* decoder to draw a horizontal band. It improves cache usage. Not
* all codecs can do that. You must check the codec capabilities
- * beforehand.
+ * beforehand. May be called by different threads at the same time,
+ * so implementations must be reentrant.
* The function is also used by hardware acceleration APIs.
* It is called at least once during frame decoding to pass
* the data needed for hardware render.
@@ -1457,6 +1474,9 @@ typedef struct AVCodecContext {
* if CODEC_CAP_DR1 is not set then get_buffer() must call
* avcodec_default_get_buffer() instead of providing buffers allocated by
* some other means.
+ * May be called from a different thread if thread_type==FF_THREAD_FRAME
+ * is set, but not by more than one thread at once, so does not need to be
+ * reentrant.
* - encoding: unused
* - decoding: Set by libavcodec, user can override.
*/
@@ -1466,6 +1486,9 @@ typedef struct AVCodecContext {
* Called to release buffers which were allocated with get_buffer.
* A released buffer can be reused in get_buffer().
* pic.data[*] must be set to NULL.
+ * May be called from a different thread if thread_type==FF_THREAD_FRAME
+ * is set, but not by more than one thread at once, so does not need to be
+ * reentrant.
* - encoding: unused
* - decoding: Set by libavcodec, user can override.
*/
@@ -1769,6 +1792,7 @@ typedef struct AVCodecContext {
#define FF_DEBUG_VIS_QP 0x00002000
#define FF_DEBUG_VIS_MB_TYPE 0x00004000
#define FF_DEBUG_BUFFERS 0x00008000
+#define FF_DEBUG_THREADS 0x00010000
/**
* debug
@@ -2768,6 +2792,34 @@ typedef struct AVCodecContext {
*/
uint8_t *subtitle_header;
int subtitle_header_size;
+
+ /**
+ * Whether this is a copy of the context which had init() called on it.
+ * This is used by multithreading - shared tables and picture pointers
+ * should be freed from the original context only.
+ * - encoding: Set by libavcodec.
+ * - decoding: Set by libavcodec.
+ */
+ int is_copy;
+
+ /**
+ * Which multithreading methods to use.
+ * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
+ * so clients which require strictly conforming DTS should not use it.
+ *
+ * - encoding: Set by user, otherwise the default is used.
+ * - decoding: Set by user, otherwise the default is used.
+ */
+ int thread_type;
+#define FF_THREAD_FRAME 1 //< Decode more than one frame at once
+#define FF_THREAD_SLICE 2 //< Decode more than one part of a single frame at once
+
+ /**
+ * Which multithreading methods are in use by the codec.
+ * - encoding: Set by libavcodec.
+ * - decoding: Set by libavcodec.
+ */
+ int active_thread_type;
} AVCodecContext;
/**
@@ -2811,6 +2863,26 @@ typedef struct AVCodec {
const int64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
uint8_t max_lowres; ///< maximum value for lowres supported by the decoder
AVClass *priv_class; ///< AVClass for the private context
+
+ /**
+ * @defgroup framethreading Frame-level threading support functions.
+ * @{
+ */
+ /**
+ * If defined, called on thread contexts when they are created.
+ * If the codec allocates writable tables in init(), re-allocate them here.
+ * priv_data will be set to a copy of the original.
+ */
+ int (*init_thread_copy)(AVCodecContext *);
+ /**
+ * Copy necessary context variables from a previous thread context to the current one.
+ * If not defined, the next thread will start automatically; otherwise, the codec
+ * must call ff_thread_finish_setup().
+ *
+ * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
+ */
+ int (*update_thread_context)(AVCodecContext *dst, AVCodecContext *src);
+ /** @} */
} AVCodec;
/**
diff --git a/libavcodec/options.c b/libavcodec/options.c
index e31a007..315f17b 100644
--- a/libavcodec/options.c
+++ b/libavcodec/options.c
@@ -250,6 +250,7 @@ static const AVOption options[]={
{"vis_qp", "visualize quantization parameter (QP), lower QP are tinted greener", 0, FF_OPT_TYPE_CONST, FF_DEBUG_VIS_QP, INT_MIN, INT_MAX, V|D, "debug"},
{"vis_mb_type", "visualize block types", 0, FF_OPT_TYPE_CONST, FF_DEBUG_VIS_MB_TYPE, INT_MIN, INT_MAX, V|D, "debug"},
{"buffers", "picture buffer allocations", 0, FF_OPT_TYPE_CONST, FF_DEBUG_BUFFERS, INT_MIN, INT_MAX, V|D, "debug"},
+{"thread_ops", "threading operations", 0, FF_OPT_TYPE_CONST, FF_DEBUG_THREADS, INT_MIN, INT_MAX, V|D, "debug"},
{"vismv", "visualize motion vectors (MVs)", OFFSET(debug_mv), FF_OPT_TYPE_INT, DEFAULT, 0, INT_MAX, V|D, "debug_mv"},
{"pf", "forward predicted MVs of P-frames", 0, FF_OPT_TYPE_CONST, FF_DEBUG_VIS_MV_P_FOR, INT_MIN, INT_MAX, V|D, "debug_mv"},
{"bf", "forward predicted MVs of B-frames", 0, FF_OPT_TYPE_CONST, FF_DEBUG_VIS_MV_B_FOR, INT_MIN, INT_MAX, V|D, "debug_mv"},
@@ -426,6 +427,9 @@ static const AVOption options[]={
{"cholesky", NULL, 0, FF_OPT_TYPE_CONST, AV_LPC_TYPE_CHOLESKY, INT_MIN, INT_MAX, A|E, "lpc_type"},
{"lpc_passes", "number of passes to use for Cholesky factorization during LPC analysis", OFFSET(lpc_passes), FF_OPT_TYPE_INT, -1, INT_MIN, INT_MAX, A|E},
{"slices", "number of slices, used in parallelized decoding", OFFSET(slices), FF_OPT_TYPE_INT, 0, 0, INT_MAX, V|E},
+{"thread_type", "select multithreading type", OFFSET(thread_type), FF_OPT_TYPE_INT, FF_THREAD_SLICE|FF_THREAD_FRAME, 0, INT_MAX, V|E|D, "thread_type"},
+{"slice", NULL, 0, FF_OPT_TYPE_CONST, FF_THREAD_SLICE, INT_MIN, INT_MAX, V|E|D, "thread_type"},
+{"frame", NULL, 0, FF_OPT_TYPE_CONST, FF_THREAD_FRAME, INT_MIN, INT_MAX, V|E|D, "thread_type"},
{NULL},
};
diff --git a/libavcodec/pthread.c b/libavcodec/pthread.c
index 1628b21..6ef9949 100644
--- a/libavcodec/pthread.c
+++ b/libavcodec/pthread.c
@@ -1,5 +1,6 @@
/*
* Copyright (c) 2004 Roman Shaposhnik
+ * Copyright (c) 2008 Alexander Strange (astrange at ithinksw.com)
*
* Many thanks to Steven M. Schultz for providing clever ideas and
* to Michael Niedermayer <michaelni at gmx.at> for writing initial
@@ -21,9 +22,17 @@
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
+
+/**
+ * @file
+ * Multithreading support functions
+ * @see doc/multithreading.txt
+ */
+
#include <pthread.h>
#include "avcodec.h"
+#include "thread.h"
typedef int (action_func)(AVCodecContext *c, void *arg);
typedef int (action_func2)(AVCodecContext *c, void *arg, int jobnr, int threadnr);
@@ -45,6 +54,72 @@ typedef struct ThreadContext {
int done;
} ThreadContext;
+/// Max number of frame buffers that can be allocated when using frame threads.
+#define MAX_BUFFERS 32
+
+/**
+ * Context used by codec threads and stored in their AVCodecContext thread_opaque.
+ */
+typedef struct PerThreadContext {
+ struct FrameThreadContext *parent;
+
+ pthread_t thread;
+ pthread_cond_t input_cond; ///< Used to wait for a new frame from the main thread.
+ pthread_cond_t progress_cond; ///< Used by child threads to wait for progress to change.
+ pthread_cond_t output_cond; ///< Used by the main thread to wait for frames to finish.
+
+ pthread_mutex_t mutex; ///< Mutex used to protect the contents of the PerThreadContext.
+ pthread_mutex_t progress_mutex; ///< Mutex used to protect frame progress values and progress_cond.
+
+ AVCodecContext *avctx; ///< Context used to decode frames passed to this thread.
+
+ AVPacket avpkt; ///< Input frame (for decoding) or output (for encoding).
+ int allocated_buf_size; ///< Size allocated for avpkt.data
+
+ AVFrame picture; ///< Output picture (for decoding) or input (for encoding).
+ int got_picture; ///< The output of got_picture_ptr from the last avcodec_decode_video() call.
+ int result; ///< The result of the last codec decode/encode() call.
+
+ enum {
+ STATE_INPUT_READY, ///< Set when the thread is awaiting a frame.
+ STATE_SETTING_UP, ///< Set before the codec has called ff_thread_finish_setup().
+ STATE_SETUP_FINISHED ///< Set after the codec has called ff_thread_finish_setup().
+ } state;
+
+ /**
+ * Array of frames passed to ff_thread_release_buffer().
+ * Frames are released after all threads referencing them are finished.
+ */
+ AVFrame released_buffers[MAX_BUFFERS];
+ int num_released_buffers;
+
+ /**
+ * Array of progress values used by ff_thread_get_buffer().
+ */
+ int progress[MAX_BUFFERS][2];
+ uint8_t progress_used[MAX_BUFFERS];
+} PerThreadContext;
+
+/**
+ * Context stored in the client AVCodecContext thread_opaque.
+ */
+typedef struct FrameThreadContext {
+ PerThreadContext *threads; ///< The contexts for each thread.
+ PerThreadContext *prev_thread; ///< The last thread submit_frame() was called on.
+
+ pthread_mutex_t buffer_mutex; ///< Mutex used to protect get/release_buffer().
+
+ int next_decoding; ///< The next context to submit a frame to.
+ int next_finished; ///< The next context to return output from.
+
+ int delaying; /**
+ * Set for the first N frames, where N is the number of threads.
+ * While it is set, ff_en/decode_frame_threaded won't return any results.
+ */
+
+ int die; ///< Set when threads should exit.
+} FrameThreadContext;
+
static void* attribute_align_arg worker(void *v)
{
AVCodecContext *avctx = v;
@@ -84,7 +159,7 @@ static av_always_inline void avcodec_thread_park_workers(ThreadContext *c, int t
pthread_mutex_unlock(&c->current_job_lock);
}
-void avcodec_thread_free(AVCodecContext *avctx)
+static void thread_free(AVCodecContext *avctx)
{
ThreadContext *c = avctx->thread_opaque;
int i;
@@ -109,6 +184,9 @@ static int avcodec_thread_execute(AVCodecContext *avctx, action_func* func, void
ThreadContext *c= avctx->thread_opaque;
int dummy_ret;
+ if (!(avctx->active_thread_type&FF_THREAD_SLICE) || avctx->thread_count <= 1)
+ return avcodec_default_execute(avctx, func, arg, ret, job_count, job_size);
+
if (job_count <= 0)
return 0;
@@ -140,10 +218,11 @@ static int avcodec_thread_execute2(AVCodecContext *avctx, action_func2* func2, v
return avcodec_thread_execute(avctx, NULL, arg, ret, job_count, 0);
}
-int avcodec_thread_init(AVCodecContext *avctx, int thread_count)
+static int thread_init(AVCodecContext *avctx)
{
int i;
ThreadContext *c;
+ int thread_count = avctx->thread_count;
avctx->thread_count = thread_count;
@@ -184,3 +263,576 @@ int avcodec_thread_init(AVCodecContext *avctx, int thread_count)
avctx->execute2 = avcodec_thread_execute2;
return 0;
}
+
+/**
+ * Codec worker thread.
+ *
+ * Automatically calls ff_thread_finish_setup() if the codec does
+ * not provide an update_thread_context method, or if the codec returns
+ * before calling it.
+ */
+static attribute_align_arg void *frame_worker_thread(void *arg)
+{
+ PerThreadContext *p = arg;
+ FrameThreadContext *fctx = p->parent;
+ AVCodecContext *avctx = p->avctx;
+ AVCodec *codec = avctx->codec;
+
+ while (1) {
+ if (p->state == STATE_INPUT_READY && !fctx->die) {
+ pthread_mutex_lock(&p->mutex);
+ while (p->state == STATE_INPUT_READY && !fctx->die)
+ pthread_cond_wait(&p->input_cond, &p->mutex);
+ pthread_mutex_unlock(&p->mutex);
+ }
+
+ if (fctx->die) break;
+
+ if (!codec->update_thread_context) ff_thread_finish_setup(avctx);
+
+ pthread_mutex_lock(&p->mutex);
+ p->result = codec->decode(avctx, &p->picture, &p->got_picture, &p->avpkt);
+
+ if (p->state == STATE_SETTING_UP) ff_thread_finish_setup(avctx);
+
+ p->state = STATE_INPUT_READY;
+
+ pthread_mutex_lock(&p->progress_mutex);
+ pthread_cond_signal(&p->output_cond);
+ pthread_mutex_unlock(&p->progress_mutex);
+
+ pthread_mutex_unlock(&p->mutex);
+ };
+
+ return NULL;
+}
+
+/**
+ * Updates the next thread's AVCodecContext with values from the reference thread's context.
+ *
+ * @param dst The destination context.
+ * @param src The source context.
+ * @param for_user 0 if the destination is a codec thread, 1 if the destination is the user's thread
+ */
+static int update_context_from_thread(AVCodecContext *dst, AVCodecContext *src, int for_user)
+{
+ int err = 0;
+
+ if (dst != src) {
+ dst->sub_id = src->sub_id;
+ dst->time_base = src->time_base;
+ dst->width = src->width;
+ dst->height = src->height;
+ dst->pix_fmt = src->pix_fmt;
+
+ dst->has_b_frames = src->has_b_frames;
+ dst->idct_algo = src->idct_algo;
+ dst->slice_count = src->slice_count;
+
+ dst->bits_per_coded_sample = src->bits_per_coded_sample;
+ dst->sample_aspect_ratio = src->sample_aspect_ratio;
+ dst->dtg_active_format = src->dtg_active_format;
+
+ dst->profile = src->profile;
+ dst->level = src->level;
+
+ dst->bits_per_raw_sample = src->bits_per_raw_sample;
+ dst->ticks_per_frame = src->ticks_per_frame;
+ dst->color_primaries = src->color_primaries;
+
+ dst->color_trc = src->color_trc;
+ dst->colorspace = src->colorspace;
+ dst->color_range = src->color_range;
+ dst->chroma_sample_location = src->chroma_sample_location;
+ }
+
+ if (for_user) {
+ dst->coded_frame = src->coded_frame;
+ dst->has_b_frames += src->thread_count - 1;
+ } else {
+ if (dst->codec->update_thread_context)
+ err = dst->codec->update_thread_context(dst, src);
+ }
+
+ return err;
+}
+
+/**
+ * Update the next thread's AVCodecContext with values set by the user.
+ *
+ * @param dst The destination context.
+ * @param src The source context.
+ */
+static void update_context_from_user(AVCodecContext *dst, AVCodecContext *src)
+{
+#define copy_fields(s, e) memcpy(&dst->s, &src->s, (char*)&dst->e - (char*)&dst->s);
+ dst->flags = src->flags;
+
+ dst->draw_horiz_band= src->draw_horiz_band;
+ dst->get_buffer = src->get_buffer;
+ dst->release_buffer = src->release_buffer;
+
+ dst->opaque = src->opaque;
+ dst->hurry_up = src->hurry_up;
+ dst->dsp_mask = src->dsp_mask;
+ dst->debug = src->debug;
+ dst->debug_mv = src->debug_mv;
+
+ dst->slice_flags = src->slice_flags;
+ dst->flags2 = src->flags2;
+
+ copy_fields(skip_loop_filter, bidir_refine);
+
+ dst->frame_number = src->frame_number;
+ dst->reordered_opaque = src->reordered_opaque;
+#undef copy_fields
+}
+
+static void free_progress(AVFrame *f)
+{
+ PerThreadContext *p = f->owner->thread_opaque;
+ int *progress = f->thread_opaque;
+
+ p->progress_used[(progress - p->progress[0]) / 2] = 0;
+}
+
+static void release_delayed_buffers(PerThreadContext *p)
+{
+ FrameThreadContext *fctx = p->parent;
+
+ while (p->num_released_buffers > 0) {
+ AVFrame *f = &p->released_buffers[--p->num_released_buffers];
+
+ pthread_mutex_lock(&fctx->buffer_mutex);
+ free_progress(f);
+ f->thread_opaque = NULL;
+
+ f->owner->release_buffer(f->owner, f);
+ pthread_mutex_unlock(&fctx->buffer_mutex);
+ }
+}
+
+static int submit_frame(PerThreadContext *p, AVPacket *avpkt)
+{
+ FrameThreadContext *fctx = p->parent;
+ PerThreadContext *prev_thread = fctx->prev_thread;
+ AVCodec *codec = p->avctx->codec;
+ uint8_t *buf = p->avpkt.data;
+
+ if (!avpkt->size && !(codec->capabilities & CODEC_CAP_DELAY)) return 0;
+
+ pthread_mutex_lock(&p->mutex);
+
+ release_delayed_buffers(p);
+
+ if (prev_thread) {
+ int err;
+ if (prev_thread->state == STATE_SETTING_UP) {
+ pthread_mutex_lock(&prev_thread->progress_mutex);
+ while (prev_thread->state == STATE_SETTING_UP)
+ pthread_cond_wait(&prev_thread->progress_cond, &prev_thread->progress_mutex);
+ pthread_mutex_unlock(&prev_thread->progress_mutex);
+ }
+
+ err = update_context_from_thread(p->avctx, prev_thread->avctx, 0);
+ if (err)
+ return err;
+ }
+
+ av_fast_malloc(&buf, &p->allocated_buf_size, avpkt->size + FF_INPUT_BUFFER_PADDING_SIZE);
+ p->avpkt = *avpkt;
+ p->avpkt.data = buf;
+ memcpy(buf, avpkt->data, avpkt->size);
+ memset(buf + avpkt->size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
+
+ p->state = STATE_SETTING_UP;
+ pthread_cond_signal(&p->input_cond);
+ pthread_mutex_unlock(&p->mutex);
+
+ fctx->prev_thread = p;
+
+ return 0;
+}
+
+int ff_thread_decode_frame(AVCodecContext *avctx,
+ AVFrame *picture, int *got_picture_ptr,
+ AVPacket *avpkt)
+{
+ FrameThreadContext *fctx = avctx->thread_opaque;
+ int finished = fctx->next_finished;
+ PerThreadContext *p;
+ int err;
+
+ /*
+ * Submit a frame to the next decoding thread.
+ */
+
+ p = &fctx->threads[fctx->next_decoding];
+ update_context_from_user(p->avctx, avctx);
+ err = submit_frame(p, avpkt);
+ if (err) return err;
+
+ fctx->next_decoding++;
+
+ /*
+ * If we're still receiving the initial frames, don't return a picture.
+ */
+
+ if (fctx->delaying && avpkt->size) {
+ if (fctx->next_decoding >= (avctx->thread_count-1)) fctx->delaying = 0;
+
+ *got_picture_ptr=0;
+ return 0;
+ }
+
+ /*
+ * Return the next available picture from the oldest thread.
+ * If we're at the end of the stream, then we have to skip threads that
+ * didn't output a picture, because we don't want to accidentally signal
+ * EOF (avpkt->size == 0 && *got_picture_ptr == 0).
+ */
+
+ do {
+ p = &fctx->threads[finished++];
+
+ if (p->state != STATE_INPUT_READY) {
+ pthread_mutex_lock(&p->progress_mutex);
+ while (p->state != STATE_INPUT_READY)
+ pthread_cond_wait(&p->output_cond, &p->progress_mutex);
+ pthread_mutex_unlock(&p->progress_mutex);
+ }
+
+ *picture = p->picture;
+ *got_picture_ptr = p->got_picture;
+
+ avcodec_get_frame_defaults(&p->picture);
+ p->got_picture = 0;
+
+ if (finished >= avctx->thread_count) finished = 0;
+ } while (!avpkt->size && !*got_picture_ptr && finished != fctx->next_finished);
+
+ update_context_from_thread(avctx, p->avctx, 1);
+
+ if (fctx->next_decoding >= avctx->thread_count) fctx->next_decoding = 0;
+
+ fctx->next_finished = finished;
+
+ return p->result;
+}
+
+void ff_thread_report_progress(AVFrame *f, int n, int field)
+{
+ PerThreadContext *p;
+ int *progress = f->thread_opaque;
+
+ if (!progress || progress[field] >= n) return;
+
+ p = f->owner->thread_opaque;
+
+ if (f->owner->debug&FF_DEBUG_THREADS)
+ av_log(f->owner, AV_LOG_DEBUG, "%p finished %d field %d\n", progress, n, field);
+
+ pthread_mutex_lock(&p->progress_mutex);
+ progress[field] = n;
+ pthread_cond_broadcast(&p->progress_cond);
+ pthread_mutex_unlock(&p->progress_mutex);
+}
+
+void ff_thread_await_progress(AVFrame *f, int n, int field)
+{
+ PerThreadContext *p;
+ int *progress = f->thread_opaque;
+
+ if (!progress || progress[field] >= n) return;
+
+ p = f->owner->thread_opaque;
+
+ if (f->owner->debug&FF_DEBUG_THREADS)
+ av_log(f->owner, AV_LOG_DEBUG, "thread awaiting %d field %d from %p\n", n, field, progress);
+
+ pthread_mutex_lock(&p->progress_mutex);
+ while (progress[field] < n)
+ pthread_cond_wait(&p->progress_cond, &p->progress_mutex);
+ pthread_mutex_unlock(&p->progress_mutex);
+}
+
+void ff_thread_finish_setup(AVCodecContext *avctx) {
+ PerThreadContext *p = avctx->thread_opaque;
+
+ if (!(avctx->active_thread_type&FF_THREAD_FRAME)) return;
+
+ pthread_mutex_lock(&p->progress_mutex);
+ p->state = STATE_SETUP_FINISHED;
+ pthread_cond_broadcast(&p->progress_cond);
+ pthread_mutex_unlock(&p->progress_mutex);
+}
+
+/// Waits for all threads to finish.
+static void park_frame_worker_threads(FrameThreadContext *fctx, int thread_count)
+{
+ int i;
+
+ for (i = 0; i < thread_count; i++) {
+ PerThreadContext *p = &fctx->threads[i];
+
+ if (p->state != STATE_INPUT_READY) {
+ pthread_mutex_lock(&p->progress_mutex);
+ while (p->state != STATE_INPUT_READY)
+ pthread_cond_wait(&p->output_cond, &p->progress_mutex);
+ pthread_mutex_unlock(&p->progress_mutex);
+ }
+ }
+}
+
+static void frame_thread_free(AVCodecContext *avctx, int thread_count)
+{
+ FrameThreadContext *fctx = avctx->thread_opaque;
+ AVCodec *codec = avctx->codec;
+ int i;
+
+ park_frame_worker_threads(fctx, thread_count);
+
+ if (fctx->prev_thread)
+ update_context_from_thread(fctx->threads->avctx, fctx->prev_thread->avctx, 0);
+
+ fctx->die = 1;
+
+ for (i = 0; i < thread_count; i++) {
+ PerThreadContext *p = &fctx->threads[i];
+
+ pthread_mutex_lock(&p->mutex);
+ pthread_cond_signal(&p->input_cond);
+ pthread_mutex_unlock(&p->mutex);
+
+ pthread_join(p->thread, NULL);
+
+ if (codec->close)
+ codec->close(p->avctx);
+
+ release_delayed_buffers(p);
+ }
+
+ for (i = 0; i < thread_count; i++) {
+ PerThreadContext *p = &fctx->threads[i];
+
+ avcodec_default_free_buffers(p->avctx);
+
+ pthread_mutex_destroy(&p->mutex);
+ pthread_mutex_destroy(&p->progress_mutex);
+ pthread_cond_destroy(&p->input_cond);
+ pthread_cond_destroy(&p->progress_cond);
+ pthread_cond_destroy(&p->output_cond);
+ av_freep(&p->avpkt.data);
+
+ if (i)
+ av_freep(&p->avctx->priv_data);
+
+ av_freep(&p->avctx);
+ }
+
+ av_freep(&fctx->threads);
+ pthread_mutex_destroy(&fctx->buffer_mutex);
+ av_freep(&avctx->thread_opaque);
+}
+
+static int frame_thread_init(AVCodecContext *avctx)
+{
+ int thread_count = avctx->thread_count, err = 0;
+ AVCodec *codec = avctx->codec;
+ AVCodecContext *src = avctx;
+ FrameThreadContext *fctx;
+ int i;
+
+ avctx->thread_opaque = fctx = av_mallocz(sizeof(FrameThreadContext));
+
+ fctx->threads = av_mallocz(sizeof(PerThreadContext) * thread_count);
+ pthread_mutex_init(&fctx->buffer_mutex, NULL);
+ fctx->delaying = 1;
+
+ for (i = 0; i < thread_count; i++) {
+ AVCodecContext *copy = av_malloc(sizeof(AVCodecContext));
+ PerThreadContext *p = &fctx->threads[i];
+
+ pthread_mutex_init(&p->mutex, NULL);
+ pthread_mutex_init(&p->progress_mutex, NULL);
+ pthread_cond_init(&p->input_cond, NULL);
+ pthread_cond_init(&p->progress_cond, NULL);
+ pthread_cond_init(&p->output_cond, NULL);
+
+ p->parent = fctx;
+ p->avctx = copy;
+
+ *copy = *src;
+ copy->thread_opaque = p;
+
+ if (!i) {
+ src = copy;
+
+ if (codec->init)
+ err = codec->init(copy);
+
+ update_context_from_thread(avctx, copy, 1);
+ } else {
+ copy->is_copy = 1;
+ copy->priv_data = av_malloc(codec->priv_data_size);
+ memcpy(copy->priv_data, src->priv_data, codec->priv_data_size);
+
+ if (codec->init_thread_copy)
+ err = codec->init_thread_copy(copy);
+ }
+
+ if (err) goto error;
+
+ pthread_create(&p->thread, NULL, frame_worker_thread, p);
+ }
+
+ return 0;
+
+error:
+ frame_thread_free(avctx, i+1);
+
+ return err;
+}
+
+void ff_thread_flush(AVCodecContext *avctx)
+{
+ FrameThreadContext *fctx = avctx->thread_opaque;
+
+ if (!avctx->thread_opaque) return;
+
+ park_frame_worker_threads(fctx, avctx->thread_count);
+
+ if (fctx->prev_thread)
+ update_context_from_thread(fctx->threads->avctx, fctx->prev_thread->avctx, 0);
+
+ fctx->next_decoding = fctx->next_finished = 0;
+ fctx->delaying = 1;
+ fctx->prev_thread = NULL;
+}
+
+static int *allocate_progress(PerThreadContext *p)
+{
+ int i;
+
+ for (i = 0; i < MAX_BUFFERS; i++)
+ if (!p->progress_used[i]) break;
+
+ if (i == MAX_BUFFERS) {
+ av_log(p->avctx, AV_LOG_ERROR, "allocate_progress() overflow\n");
+ return NULL;
+ }
+
+ p->progress_used[i] = 1;
+
+ return p->progress[i];
+}
+
+int ff_thread_get_buffer(AVCodecContext *avctx, AVFrame *f)
+{
+ PerThreadContext *p = avctx->thread_opaque;
+ int *progress, err;
+
+ f->owner = avctx;
+
+ if (!(avctx->active_thread_type&FF_THREAD_FRAME)) {
+ f->thread_opaque = NULL;
+ return avctx->get_buffer(avctx, f);
+ }
+
+ pthread_mutex_lock(&p->parent->buffer_mutex);
+ f->thread_opaque = progress = allocate_progress(p);
+
+ if (!progress) {
+ pthread_mutex_unlock(&p->parent->buffer_mutex);
+ return -1;
+ }
+
+ progress[0] =
+ progress[1] = -1;
+
+ err = avctx->get_buffer(avctx, f);
+ pthread_mutex_unlock(&p->parent->buffer_mutex);
+
+ /*
+ * Buffer age is difficult to keep track of between
+ * multiple threads, and the optimizations it allows
+ * are not worth the effort. It is disabled for now.
+ */
+ f->age = INT_MAX;
+
+ return err;
+}
+
+void ff_thread_release_buffer(AVCodecContext *avctx, AVFrame *f)
+{
+ PerThreadContext *p = avctx->thread_opaque;
+
+ if (!(avctx->active_thread_type&FF_THREAD_FRAME)) {
+ avctx->release_buffer(avctx, f);
+ return;
+ }
+
+ if (p->num_released_buffers >= MAX_BUFFERS) {
+ av_log(p->avctx, AV_LOG_ERROR, "too many thread_release_buffer calls!\n");
+ return;
+ }
+
+ if(avctx->debug & FF_DEBUG_BUFFERS)
+ av_log(avctx, AV_LOG_DEBUG, "thread_release_buffer called on pic %p, %d buffers used\n",
+ f, f->owner->internal_buffer_count);
+
+ p->released_buffers[p->num_released_buffers++] = *f;
+ memset(f->data, 0, sizeof(f->data));
+}
+
+/**
+ * Set the threading algorithms used.
+ *
+ * Threading requires more than one thread.
+ * Frame threading requires entire frames to be passed to the codec,
+ * and is incompatible with low_delay.
+ *
+ * @param avctx The context.
+ */
+static void validate_thread_parameters(AVCodecContext *avctx)
+{
+ int frame_threading_supported = (avctx->codec->capabilities & CODEC_CAP_FRAME_THREADS)
+ && !(avctx->flags & CODEC_FLAG_TRUNCATED)
+ && !(avctx->flags & CODEC_FLAG_LOW_DELAY)
+ && !(avctx->flags2 & CODEC_FLAG2_CHUNKS);
+ if (avctx->thread_count == 1)
+ avctx->active_thread_type = 0;
+ else if (frame_threading_supported && (avctx->thread_type & FF_THREAD_FRAME))
+ avctx->active_thread_type = FF_THREAD_FRAME;
+ else
+ avctx->active_thread_type = FF_THREAD_SLICE;
+}
+
+int avcodec_thread_init(AVCodecContext *avctx, int thread_count)
+{
+ if (avctx->thread_opaque) {
+ av_log(avctx, AV_LOG_ERROR, "avcodec_thread_init is ignored after avcodec_open\n");
+ return -1;
+ }
+
+ avctx->thread_count = FFMAX(1, thread_count);
+
+ if (avctx->codec) {
+ validate_thread_parameters(avctx);
+
+ if (avctx->active_thread_type&FF_THREAD_SLICE)
+ return thread_init(avctx);
+ else if (avctx->active_thread_type&FF_THREAD_FRAME)
+ return frame_thread_init(avctx);
+ }
+
+ return 0;
+}
+
+void avcodec_thread_free(AVCodecContext *avctx)
+{
+ if (avctx->active_thread_type&FF_THREAD_FRAME)
+ frame_thread_free(avctx, avctx->thread_count);
+ else
+ thread_free(avctx);
+}
diff --git a/libavcodec/thread.h b/libavcodec/thread.h
new file mode 100644
index 0000000..ac370bd
--- /dev/null
+++ b/libavcodec/thread.h
@@ -0,0 +1,98 @@
+/*
+ * Copyright (c) 2008 Alexander Strange <astrange at ithinksw.com>
+ *
+ * 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
+ * Multithreading support functions
+ * @author Alexander Strange <astrange at ithinksw.com>
+ */
+
+#ifndef AVCODEC_THREAD_H
+#define AVCODEC_THREAD_H
+
+#include "config.h"
+#include "avcodec.h"
+
+/**
+ * Waits for decoding threads to finish and resets internal
+ * state. Called by avcodec_flush_buffers().
+ *
+ * @param avctx The context.
+ */
+void ff_thread_flush(AVCodecContext *avctx);
+
+/**
+ * Submits a new frame to a decoding thread.
+ * Returns the next available frame in picture. *got_picture_ptr
+ * will be 0 if none is available.
+ *
+ * Parameters are the same as avcodec_decode_video2().
+ */
+int ff_thread_decode_frame(AVCodecContext *avctx, AVFrame *picture,
+ int *got_picture_ptr, AVPacket *avpkt);
+
+/**
+ * Codecs which define update_thread_context should call this
+ * when they are ready for the next thread to start decoding
+ * the next frame. After calling it, do not change any variables
+ * read by the update_thread_context method.
+ *
+ * @param avctx The context.
+ */
+void ff_thread_finish_setup(AVCodecContext *avctx);
+
+/**
+ * Call this when some part of the picture is finished decoding.
+ * Later calls with lower values of progress have no effect.
+ *
+ * @param f The picture being decoded.
+ * @param progress Value, in arbitrary units, of how much of the picture has decoded.
+ * @param field The field being decoded, for field-picture codecs.
+ * 0 for top field or frame pictures, 1 for bottom field.
+ */
+void ff_thread_report_progress(AVFrame *f, int progress, int field);
+
+/**
+ * Call this before accessing some part of a picture.
+ *
+ * @param f The picture being referenced.
+ * @param progress Value, in arbitrary units, to wait for.
+ * @param field The field being referenced, for field-picture codecs.
+ * 0 for top field or frame pictures, 1 for bottom field.
+ */
+void ff_thread_await_progress(AVFrame *f, int progress, int field);
+
+/**
+ * Call this function instead of avctx->get_buffer(f).
+ *
+ * @param avctx The current context.
+ * @param f The frame to write into.
+ */
+int ff_thread_get_buffer(AVCodecContext *avctx, AVFrame *f);
+
+/**
+ * Call this function instead of avctx->release_buffer(f).
+ *
+ * @param avctx The current context.
+ * @param f The picture being released.
+ */
+void ff_thread_release_buffer(AVCodecContext *avctx, AVFrame *f);
+
+#endif /* AVCODEC_THREAD_H */
diff --git a/libavcodec/utils.c b/libavcodec/utils.c
index 3875140..c931484 100644
--- a/libavcodec/utils.c
+++ b/libavcodec/utils.c
@@ -36,6 +36,7 @@
#include "dsputil.h"
#include "libavutil/opt.h"
#include "imgconvert.h"
+#include "thread.h"
#include "audioconvert.h"
#include "internal.h"
#include <stdlib.h>
@@ -256,6 +257,11 @@ int avcodec_default_get_buffer(AVCodecContext *s, AVFrame *pic){
(*picture_number)++;
if(buf->base[0] && (buf->width != w || buf->height != h || buf->pix_fmt != s->pix_fmt)){
+ if(s->active_thread_type&FF_THREAD_FRAME) {
+ av_log_missing_feature(s, "Width/height changing with frame threads is", 0);
+ return -1;
+ }
+
for(i=0; i<4; i++){
av_freep(&buf->base[i]);
buf->data[i]= NULL;
@@ -517,18 +523,29 @@ int attribute_align_arg avcodec_open(AVCodecContext *avctx, AVCodec *codec)
goto free_and_end;
}
avctx->frame_number = 0;
+
+ if (HAVE_THREADS && !avctx->thread_opaque) {
+ ret = avcodec_thread_init(avctx, avctx->thread_count);
+ if (ret < 0) {
+ goto free_and_end;
+ }
+ }
+
if (avctx->codec->max_lowres < avctx->lowres) {
av_log(avctx, AV_LOG_ERROR, "The maximum value for lowres supported by the decoder is %d\n",
avctx->codec->max_lowres);
goto free_and_end;
}
- if(avctx->codec->init){
- ret = avctx->codec->init(avctx);
- if (ret < 0) {
- goto free_and_end;
+ if(avctx->codec->init && !(avctx->active_thread_type&FF_THREAD_FRAME)){
+ if(avctx->codec->init){
+ ret = avctx->codec->init(avctx);
+ if (ret < 0) {
+ goto free_and_end;
+ }
}
}
+
ret=0;
end:
entangled_thread_counter--;
@@ -618,8 +635,11 @@ int attribute_align_arg avcodec_decode_video2(AVCodecContext *avctx, AVFrame *pi
*got_picture_ptr= 0;
if((avctx->coded_width||avctx->coded_height) && av_image_check_size(avctx->coded_width, avctx->coded_height, 0, avctx))
return -1;
- if((avctx->codec->capabilities & CODEC_CAP_DELAY) || avpkt->size){
- ret = avctx->codec->decode(avctx, picture, got_picture_ptr,
+ if((avctx->codec->capabilities & CODEC_CAP_DELAY) || avpkt->size || (avctx->active_thread_type&FF_THREAD_FRAME)){
+ if (HAVE_PTHREADS && avctx->active_thread_type&FF_THREAD_FRAME)
+ ret = ff_thread_decode_frame(avctx, picture, got_picture_ptr,
+ avpkt);
+ else ret = avctx->codec->decode(avctx, picture, got_picture_ptr,
avpkt);
emms_c(); //needed to avoid an emms_c() call before every return;
@@ -737,7 +757,7 @@ av_cold int avcodec_close(AVCodecContext *avctx)
if (HAVE_THREADS && avctx->thread_opaque)
avcodec_thread_free(avctx);
- if (avctx->codec && avctx->codec->close)
+ if (avctx->codec && avctx->codec->close && !(avctx->active_thread_type&FF_THREAD_FRAME))
avctx->codec->close(avctx);
avcodec_default_free_buffers(avctx);
avctx->coded_frame = NULL;
@@ -745,6 +765,7 @@ av_cold int avcodec_close(AVCodecContext *avctx)
if(avctx->codec && avctx->codec->encode)
av_freep(&avctx->extradata);
avctx->codec = NULL;
+ avctx->active_thread_type = 0;
entangled_thread_counter--;
/* Release any user-supplied mutex. */
@@ -985,6 +1006,8 @@ void avcodec_init(void)
void avcodec_flush_buffers(AVCodecContext *avctx)
{
+ if(HAVE_PTHREADS && avctx->active_thread_type&FF_THREAD_FRAME)
+ ff_thread_flush(avctx);
if(avctx->codec->flush)
avctx->codec->flush(avctx);
}
@@ -1185,3 +1208,30 @@ unsigned int ff_toupper4(unsigned int x)
+ (toupper((x>>16)&0xFF)<<16)
+ (toupper((x>>24)&0xFF)<<24);
}
+
+#if !HAVE_PTHREADS
+
+int ff_thread_get_buffer(AVCodecContext *avctx, AVFrame *f)
+{
+ f->owner = avctx;
+ return avctx->get_buffer(avctx, f);
+}
+
+void ff_thread_release_buffer(AVCodecContext *avctx, AVFrame *f)
+{
+ f->owner->release_buffer(f->owner, f);
+}
+
+void ff_thread_finish_setup(AVCodecContext *avctx)
+{
+}
+
+void ff_thread_report_progress(AVFrame *f, int progress, int field)
+{
+}
+
+void ff_thread_await_progress(AVFrame *f, int progress, int field)
+{
+}
+
+#endif
diff --git a/libavcodec/w32thread.c b/libavcodec/w32thread.c
index f7a1430..007508e 100644
--- a/libavcodec/w32thread.c
+++ b/libavcodec/w32thread.c
@@ -129,7 +129,13 @@ int avcodec_thread_init(AVCodecContext *s, int thread_count){
ThreadContext *c;
uint32_t threadid;
+ if(!(s->thread_type & FF_THREAD_SLICE)){
+ av_log(s, AV_LOG_WARNING, "The requested thread algorithm is not supported with this thread library.\n");
+ return 0;
+ }
+
s->thread_count= thread_count;
+ s->active_thread_type= FF_THREAD_SLICE;
if (thread_count <= 1)
return 0;
diff --git a/libavformat/utils.c b/libavformat/utils.c
index 8fcbe96..0b5d89c 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -913,6 +913,11 @@ static void compute_pkt_fields(AVFormatContext *s, AVStream *st,
/* do we have a video B-frame ? */
delay= st->codec->has_b_frames;
presentation_delayed = 0;
+
+ // ignore delay caused by frame threading
+ if (delay && st->codec->active_thread_type&FF_THREAD_FRAME)
+ delay -= st->codec->thread_count-1;
+
/* XXX: need has_b_frame, but cannot get it if the codec is
not initialized */
if (delay &&
diff --git a/libavutil/internal.h b/libavutil/internal.h
index 9c4ba7e..48854f3 100644
--- a/libavutil/internal.h
+++ b/libavutil/internal.h
@@ -231,4 +231,15 @@
type ff_##name args
#endif
+/**
+ * Returns NULL if a threading library has not been enabled.
+ * Used to disable threading functions in AVCodec definitions
+ * when not needed.
+ */
+#if HAVE_THREADS
+# define ONLY_IF_THREADS_ENABLED(x) x
+#else
+# define ONLY_IF_THREADS_ENABLED(x) NULL
+#endif
+
#endif /* AVUTIL_INTERNAL_H */
--
1.7.3.1
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